FreeBSD/Linux Kernel Cross Reference
sys/kern/vfs_subr.c
1 /*-
2 * Copyright (c) 1989, 1993
3 * The Regents of the University of California. All rights reserved.
4 * (c) UNIX System Laboratories, Inc.
5 * All or some portions of this file are derived from material licensed
6 * to the University of California by American Telephone and Telegraph
7 * Co. or Unix System Laboratories, Inc. and are reproduced herein with
8 * the permission of UNIX System Laboratories, Inc.
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 * 4. Neither the name of the University nor the names of its contributors
19 * may be used to endorse or promote products derived from this software
20 * without specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * SUCH DAMAGE.
33 *
34 * @(#)vfs_subr.c 8.31 (Berkeley) 5/26/95
35 */
36
37 /*
38 * External virtual filesystem routines
39 */
40
41 #include <sys/cdefs.h>
42 __FBSDID("$FreeBSD: releng/8.1/sys/kern/vfs_subr.c 209319 2010-06-18 22:06:49Z pjd $");
43
44 #include "opt_ddb.h"
45
46 #include <sys/param.h>
47 #include <sys/systm.h>
48 #include <sys/bio.h>
49 #include <sys/buf.h>
50 #include <sys/condvar.h>
51 #include <sys/conf.h>
52 #include <sys/dirent.h>
53 #include <sys/event.h>
54 #include <sys/eventhandler.h>
55 #include <sys/extattr.h>
56 #include <sys/file.h>
57 #include <sys/fcntl.h>
58 #include <sys/jail.h>
59 #include <sys/kdb.h>
60 #include <sys/kernel.h>
61 #include <sys/kthread.h>
62 #include <sys/lockf.h>
63 #include <sys/malloc.h>
64 #include <sys/mount.h>
65 #include <sys/namei.h>
66 #include <sys/priv.h>
67 #include <sys/reboot.h>
68 #include <sys/sleepqueue.h>
69 #include <sys/stat.h>
70 #include <sys/sysctl.h>
71 #include <sys/syslog.h>
72 #include <sys/vmmeter.h>
73 #include <sys/vnode.h>
74
75 #include <machine/stdarg.h>
76
77 #include <security/mac/mac_framework.h>
78
79 #include <vm/vm.h>
80 #include <vm/vm_object.h>
81 #include <vm/vm_extern.h>
82 #include <vm/pmap.h>
83 #include <vm/vm_map.h>
84 #include <vm/vm_page.h>
85 #include <vm/vm_kern.h>
86 #include <vm/uma.h>
87
88 #ifdef DDB
89 #include <ddb/ddb.h>
90 #endif
91
92 #define WI_MPSAFEQ 0
93 #define WI_GIANTQ 1
94
95 static MALLOC_DEFINE(M_NETADDR, "subr_export_host", "Export host address structure");
96
97 static void delmntque(struct vnode *vp);
98 static int flushbuflist(struct bufv *bufv, int flags, struct bufobj *bo,
99 int slpflag, int slptimeo);
100 static void syncer_shutdown(void *arg, int howto);
101 static int vtryrecycle(struct vnode *vp);
102 static void vbusy(struct vnode *vp);
103 static void vinactive(struct vnode *, struct thread *);
104 static void v_incr_usecount(struct vnode *);
105 static void v_decr_usecount(struct vnode *);
106 static void v_decr_useonly(struct vnode *);
107 static void v_upgrade_usecount(struct vnode *);
108 static void vfree(struct vnode *);
109 static void vnlru_free(int);
110 static void vgonel(struct vnode *);
111 static void vfs_knllock(void *arg);
112 static void vfs_knlunlock(void *arg);
113 static void vfs_knl_assert_locked(void *arg);
114 static void vfs_knl_assert_unlocked(void *arg);
115 static void destroy_vpollinfo(struct vpollinfo *vi);
116
117 /*
118 * Number of vnodes in existence. Increased whenever getnewvnode()
119 * allocates a new vnode, decreased on vdestroy() called on VI_DOOMed
120 * vnode.
121 */
122 static unsigned long numvnodes;
123
124 SYSCTL_LONG(_vfs, OID_AUTO, numvnodes, CTLFLAG_RD, &numvnodes, 0, "");
125
126 /*
127 * Conversion tables for conversion from vnode types to inode formats
128 * and back.
129 */
130 enum vtype iftovt_tab[16] = {
131 VNON, VFIFO, VCHR, VNON, VDIR, VNON, VBLK, VNON,
132 VREG, VNON, VLNK, VNON, VSOCK, VNON, VNON, VBAD,
133 };
134 int vttoif_tab[10] = {
135 0, S_IFREG, S_IFDIR, S_IFBLK, S_IFCHR, S_IFLNK,
136 S_IFSOCK, S_IFIFO, S_IFMT, S_IFMT
137 };
138
139 /*
140 * List of vnodes that are ready for recycling.
141 */
142 static TAILQ_HEAD(freelst, vnode) vnode_free_list;
143
144 /*
145 * Free vnode target. Free vnodes may simply be files which have been stat'd
146 * but not read. This is somewhat common, and a small cache of such files
147 * should be kept to avoid recreation costs.
148 */
149 static u_long wantfreevnodes;
150 SYSCTL_LONG(_vfs, OID_AUTO, wantfreevnodes, CTLFLAG_RW, &wantfreevnodes, 0, "");
151 /* Number of vnodes in the free list. */
152 static u_long freevnodes;
153 SYSCTL_LONG(_vfs, OID_AUTO, freevnodes, CTLFLAG_RD, &freevnodes, 0, "");
154
155 static int vlru_allow_cache_src;
156 SYSCTL_INT(_vfs, OID_AUTO, vlru_allow_cache_src, CTLFLAG_RW,
157 &vlru_allow_cache_src, 0, "Allow vlru to reclaim source vnode");
158
159 /*
160 * Various variables used for debugging the new implementation of
161 * reassignbuf().
162 * XXX these are probably of (very) limited utility now.
163 */
164 static int reassignbufcalls;
165 SYSCTL_INT(_vfs, OID_AUTO, reassignbufcalls, CTLFLAG_RW, &reassignbufcalls, 0, "");
166
167 /*
168 * Cache for the mount type id assigned to NFS. This is used for
169 * special checks in nfs/nfs_nqlease.c and vm/vnode_pager.c.
170 */
171 int nfs_mount_type = -1;
172
173 /* To keep more than one thread at a time from running vfs_getnewfsid */
174 static struct mtx mntid_mtx;
175
176 /*
177 * Lock for any access to the following:
178 * vnode_free_list
179 * numvnodes
180 * freevnodes
181 */
182 static struct mtx vnode_free_list_mtx;
183
184 /* Publicly exported FS */
185 struct nfs_public nfs_pub;
186
187 /* Zone for allocation of new vnodes - used exclusively by getnewvnode() */
188 static uma_zone_t vnode_zone;
189 static uma_zone_t vnodepoll_zone;
190
191 /* Set to 1 to print out reclaim of active vnodes */
192 int prtactive;
193
194 /*
195 * The workitem queue.
196 *
197 * It is useful to delay writes of file data and filesystem metadata
198 * for tens of seconds so that quickly created and deleted files need
199 * not waste disk bandwidth being created and removed. To realize this,
200 * we append vnodes to a "workitem" queue. When running with a soft
201 * updates implementation, most pending metadata dependencies should
202 * not wait for more than a few seconds. Thus, mounted on block devices
203 * are delayed only about a half the time that file data is delayed.
204 * Similarly, directory updates are more critical, so are only delayed
205 * about a third the time that file data is delayed. Thus, there are
206 * SYNCER_MAXDELAY queues that are processed round-robin at a rate of
207 * one each second (driven off the filesystem syncer process). The
208 * syncer_delayno variable indicates the next queue that is to be processed.
209 * Items that need to be processed soon are placed in this queue:
210 *
211 * syncer_workitem_pending[syncer_delayno]
212 *
213 * A delay of fifteen seconds is done by placing the request fifteen
214 * entries later in the queue:
215 *
216 * syncer_workitem_pending[(syncer_delayno + 15) & syncer_mask]
217 *
218 */
219 static int syncer_delayno;
220 static long syncer_mask;
221 LIST_HEAD(synclist, bufobj);
222 static struct synclist *syncer_workitem_pending[2];
223 /*
224 * The sync_mtx protects:
225 * bo->bo_synclist
226 * sync_vnode_count
227 * syncer_delayno
228 * syncer_state
229 * syncer_workitem_pending
230 * syncer_worklist_len
231 * rushjob
232 */
233 static struct mtx sync_mtx;
234 static struct cv sync_wakeup;
235
236 #define SYNCER_MAXDELAY 32
237 static int syncer_maxdelay = SYNCER_MAXDELAY; /* maximum delay time */
238 static int syncdelay = 30; /* max time to delay syncing data */
239 static int filedelay = 30; /* time to delay syncing files */
240 SYSCTL_INT(_kern, OID_AUTO, filedelay, CTLFLAG_RW, &filedelay, 0, "");
241 static int dirdelay = 29; /* time to delay syncing directories */
242 SYSCTL_INT(_kern, OID_AUTO, dirdelay, CTLFLAG_RW, &dirdelay, 0, "");
243 static int metadelay = 28; /* time to delay syncing metadata */
244 SYSCTL_INT(_kern, OID_AUTO, metadelay, CTLFLAG_RW, &metadelay, 0, "");
245 static int rushjob; /* number of slots to run ASAP */
246 static int stat_rush_requests; /* number of times I/O speeded up */
247 SYSCTL_INT(_debug, OID_AUTO, rush_requests, CTLFLAG_RW, &stat_rush_requests, 0, "");
248
249 /*
250 * When shutting down the syncer, run it at four times normal speed.
251 */
252 #define SYNCER_SHUTDOWN_SPEEDUP 4
253 static int sync_vnode_count;
254 static int syncer_worklist_len;
255 static enum { SYNCER_RUNNING, SYNCER_SHUTTING_DOWN, SYNCER_FINAL_DELAY }
256 syncer_state;
257
258 /*
259 * Number of vnodes we want to exist at any one time. This is mostly used
260 * to size hash tables in vnode-related code. It is normally not used in
261 * getnewvnode(), as wantfreevnodes is normally nonzero.)
262 *
263 * XXX desiredvnodes is historical cruft and should not exist.
264 */
265 int desiredvnodes;
266 SYSCTL_INT(_kern, KERN_MAXVNODES, maxvnodes, CTLFLAG_RW,
267 &desiredvnodes, 0, "Maximum number of vnodes");
268 SYSCTL_INT(_kern, OID_AUTO, minvnodes, CTLFLAG_RW,
269 &wantfreevnodes, 0, "Minimum number of vnodes (legacy)");
270 static int vnlru_nowhere;
271 SYSCTL_INT(_debug, OID_AUTO, vnlru_nowhere, CTLFLAG_RW,
272 &vnlru_nowhere, 0, "Number of times the vnlru process ran without success");
273
274 /*
275 * Macros to control when a vnode is freed and recycled. All require
276 * the vnode interlock.
277 */
278 #define VCANRECYCLE(vp) (((vp)->v_iflag & VI_FREE) && !(vp)->v_holdcnt)
279 #define VSHOULDFREE(vp) (!((vp)->v_iflag & VI_FREE) && !(vp)->v_holdcnt)
280 #define VSHOULDBUSY(vp) (((vp)->v_iflag & VI_FREE) && (vp)->v_holdcnt)
281
282
283 /*
284 * Initialize the vnode management data structures.
285 */
286 #ifndef MAXVNODES_MAX
287 #define MAXVNODES_MAX 100000
288 #endif
289 static void
290 vntblinit(void *dummy __unused)
291 {
292
293 /*
294 * Desiredvnodes is a function of the physical memory size and
295 * the kernel's heap size. Specifically, desiredvnodes scales
296 * in proportion to the physical memory size until two fifths
297 * of the kernel's heap size is consumed by vnodes and vm
298 * objects.
299 */
300 desiredvnodes = min(maxproc + cnt.v_page_count / 4, 2 * vm_kmem_size /
301 (5 * (sizeof(struct vm_object) + sizeof(struct vnode))));
302 if (desiredvnodes > MAXVNODES_MAX) {
303 if (bootverbose)
304 printf("Reducing kern.maxvnodes %d -> %d\n",
305 desiredvnodes, MAXVNODES_MAX);
306 desiredvnodes = MAXVNODES_MAX;
307 }
308 wantfreevnodes = desiredvnodes / 4;
309 mtx_init(&mntid_mtx, "mntid", NULL, MTX_DEF);
310 TAILQ_INIT(&vnode_free_list);
311 mtx_init(&vnode_free_list_mtx, "vnode_free_list", NULL, MTX_DEF);
312 vnode_zone = uma_zcreate("VNODE", sizeof (struct vnode), NULL, NULL,
313 NULL, NULL, UMA_ALIGN_PTR, 0);
314 vnodepoll_zone = uma_zcreate("VNODEPOLL", sizeof (struct vpollinfo),
315 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0);
316 /*
317 * Initialize the filesystem syncer.
318 */
319 syncer_workitem_pending[WI_MPSAFEQ] = hashinit(syncer_maxdelay, M_VNODE,
320 &syncer_mask);
321 syncer_workitem_pending[WI_GIANTQ] = hashinit(syncer_maxdelay, M_VNODE,
322 &syncer_mask);
323 syncer_maxdelay = syncer_mask + 1;
324 mtx_init(&sync_mtx, "Syncer mtx", NULL, MTX_DEF);
325 cv_init(&sync_wakeup, "syncer");
326 }
327 SYSINIT(vfs, SI_SUB_VFS, SI_ORDER_FIRST, vntblinit, NULL);
328
329
330 /*
331 * Mark a mount point as busy. Used to synchronize access and to delay
332 * unmounting. Eventually, mountlist_mtx is not released on failure.
333 */
334 int
335 vfs_busy(struct mount *mp, int flags)
336 {
337
338 MPASS((flags & ~MBF_MASK) == 0);
339 CTR3(KTR_VFS, "%s: mp %p with flags %d", __func__, mp, flags);
340
341 MNT_ILOCK(mp);
342 MNT_REF(mp);
343 /*
344 * If mount point is currenly being unmounted, sleep until the
345 * mount point fate is decided. If thread doing the unmounting fails,
346 * it will clear MNTK_UNMOUNT flag before waking us up, indicating
347 * that this mount point has survived the unmount attempt and vfs_busy
348 * should retry. Otherwise the unmounter thread will set MNTK_REFEXPIRE
349 * flag in addition to MNTK_UNMOUNT, indicating that mount point is
350 * about to be really destroyed. vfs_busy needs to release its
351 * reference on the mount point in this case and return with ENOENT,
352 * telling the caller that mount mount it tried to busy is no longer
353 * valid.
354 */
355 while (mp->mnt_kern_flag & MNTK_UNMOUNT) {
356 if (flags & MBF_NOWAIT || mp->mnt_kern_flag & MNTK_REFEXPIRE) {
357 MNT_REL(mp);
358 MNT_IUNLOCK(mp);
359 CTR1(KTR_VFS, "%s: failed busying before sleeping",
360 __func__);
361 return (ENOENT);
362 }
363 if (flags & MBF_MNTLSTLOCK)
364 mtx_unlock(&mountlist_mtx);
365 mp->mnt_kern_flag |= MNTK_MWAIT;
366 msleep(mp, MNT_MTX(mp), PVFS, "vfs_busy", 0);
367 if (flags & MBF_MNTLSTLOCK)
368 mtx_lock(&mountlist_mtx);
369 }
370 if (flags & MBF_MNTLSTLOCK)
371 mtx_unlock(&mountlist_mtx);
372 mp->mnt_lockref++;
373 MNT_IUNLOCK(mp);
374 return (0);
375 }
376
377 /*
378 * Free a busy filesystem.
379 */
380 void
381 vfs_unbusy(struct mount *mp)
382 {
383
384 CTR2(KTR_VFS, "%s: mp %p", __func__, mp);
385 MNT_ILOCK(mp);
386 MNT_REL(mp);
387 KASSERT(mp->mnt_lockref > 0, ("negative mnt_lockref"));
388 mp->mnt_lockref--;
389 if (mp->mnt_lockref == 0 && (mp->mnt_kern_flag & MNTK_DRAINING) != 0) {
390 MPASS(mp->mnt_kern_flag & MNTK_UNMOUNT);
391 CTR1(KTR_VFS, "%s: waking up waiters", __func__);
392 mp->mnt_kern_flag &= ~MNTK_DRAINING;
393 wakeup(&mp->mnt_lockref);
394 }
395 MNT_IUNLOCK(mp);
396 }
397
398 /*
399 * Lookup a mount point by filesystem identifier.
400 */
401 struct mount *
402 vfs_getvfs(fsid_t *fsid)
403 {
404 struct mount *mp;
405
406 CTR2(KTR_VFS, "%s: fsid %p", __func__, fsid);
407 mtx_lock(&mountlist_mtx);
408 TAILQ_FOREACH(mp, &mountlist, mnt_list) {
409 if (mp->mnt_stat.f_fsid.val[0] == fsid->val[0] &&
410 mp->mnt_stat.f_fsid.val[1] == fsid->val[1]) {
411 vfs_ref(mp);
412 mtx_unlock(&mountlist_mtx);
413 return (mp);
414 }
415 }
416 mtx_unlock(&mountlist_mtx);
417 CTR2(KTR_VFS, "%s: lookup failed for %p id", __func__, fsid);
418 return ((struct mount *) 0);
419 }
420
421 /*
422 * Lookup a mount point by filesystem identifier, busying it before
423 * returning.
424 */
425 struct mount *
426 vfs_busyfs(fsid_t *fsid)
427 {
428 struct mount *mp;
429 int error;
430
431 CTR2(KTR_VFS, "%s: fsid %p", __func__, fsid);
432 mtx_lock(&mountlist_mtx);
433 TAILQ_FOREACH(mp, &mountlist, mnt_list) {
434 if (mp->mnt_stat.f_fsid.val[0] == fsid->val[0] &&
435 mp->mnt_stat.f_fsid.val[1] == fsid->val[1]) {
436 error = vfs_busy(mp, MBF_MNTLSTLOCK);
437 if (error) {
438 mtx_unlock(&mountlist_mtx);
439 return (NULL);
440 }
441 return (mp);
442 }
443 }
444 CTR2(KTR_VFS, "%s: lookup failed for %p id", __func__, fsid);
445 mtx_unlock(&mountlist_mtx);
446 return ((struct mount *) 0);
447 }
448
449 /*
450 * Check if a user can access privileged mount options.
451 */
452 int
453 vfs_suser(struct mount *mp, struct thread *td)
454 {
455 int error;
456
457 /*
458 * If the thread is jailed, but this is not a jail-friendly file
459 * system, deny immediately.
460 */
461 if (!(mp->mnt_vfc->vfc_flags & VFCF_JAIL) && jailed(td->td_ucred))
462 return (EPERM);
463
464 /*
465 * If the file system was mounted outside the jail of the calling
466 * thread, deny immediately.
467 */
468 if (prison_check(td->td_ucred, mp->mnt_cred) != 0)
469 return (EPERM);
470
471 /*
472 * If file system supports delegated administration, we don't check
473 * for the PRIV_VFS_MOUNT_OWNER privilege - it will be better verified
474 * by the file system itself.
475 * If this is not the user that did original mount, we check for
476 * the PRIV_VFS_MOUNT_OWNER privilege.
477 */
478 if (!(mp->mnt_vfc->vfc_flags & VFCF_DELEGADMIN) &&
479 mp->mnt_cred->cr_uid != td->td_ucred->cr_uid) {
480 if ((error = priv_check(td, PRIV_VFS_MOUNT_OWNER)) != 0)
481 return (error);
482 }
483 return (0);
484 }
485
486 /*
487 * Get a new unique fsid. Try to make its val[0] unique, since this value
488 * will be used to create fake device numbers for stat(). Also try (but
489 * not so hard) make its val[0] unique mod 2^16, since some emulators only
490 * support 16-bit device numbers. We end up with unique val[0]'s for the
491 * first 2^16 calls and unique val[0]'s mod 2^16 for the first 2^8 calls.
492 *
493 * Keep in mind that several mounts may be running in parallel. Starting
494 * the search one past where the previous search terminated is both a
495 * micro-optimization and a defense against returning the same fsid to
496 * different mounts.
497 */
498 void
499 vfs_getnewfsid(struct mount *mp)
500 {
501 static u_int16_t mntid_base;
502 struct mount *nmp;
503 fsid_t tfsid;
504 int mtype;
505
506 CTR2(KTR_VFS, "%s: mp %p", __func__, mp);
507 mtx_lock(&mntid_mtx);
508 mtype = mp->mnt_vfc->vfc_typenum;
509 tfsid.val[1] = mtype;
510 mtype = (mtype & 0xFF) << 24;
511 for (;;) {
512 tfsid.val[0] = makedev(255,
513 mtype | ((mntid_base & 0xFF00) << 8) | (mntid_base & 0xFF));
514 mntid_base++;
515 if ((nmp = vfs_getvfs(&tfsid)) == NULL)
516 break;
517 vfs_rel(nmp);
518 }
519 mp->mnt_stat.f_fsid.val[0] = tfsid.val[0];
520 mp->mnt_stat.f_fsid.val[1] = tfsid.val[1];
521 mtx_unlock(&mntid_mtx);
522 }
523
524 /*
525 * Knob to control the precision of file timestamps:
526 *
527 * 0 = seconds only; nanoseconds zeroed.
528 * 1 = seconds and nanoseconds, accurate within 1/HZ.
529 * 2 = seconds and nanoseconds, truncated to microseconds.
530 * >=3 = seconds and nanoseconds, maximum precision.
531 */
532 enum { TSP_SEC, TSP_HZ, TSP_USEC, TSP_NSEC };
533
534 static int timestamp_precision = TSP_SEC;
535 SYSCTL_INT(_vfs, OID_AUTO, timestamp_precision, CTLFLAG_RW,
536 ×tamp_precision, 0, "");
537
538 /*
539 * Get a current timestamp.
540 */
541 void
542 vfs_timestamp(struct timespec *tsp)
543 {
544 struct timeval tv;
545
546 switch (timestamp_precision) {
547 case TSP_SEC:
548 tsp->tv_sec = time_second;
549 tsp->tv_nsec = 0;
550 break;
551 case TSP_HZ:
552 getnanotime(tsp);
553 break;
554 case TSP_USEC:
555 microtime(&tv);
556 TIMEVAL_TO_TIMESPEC(&tv, tsp);
557 break;
558 case TSP_NSEC:
559 default:
560 nanotime(tsp);
561 break;
562 }
563 }
564
565 /*
566 * Set vnode attributes to VNOVAL
567 */
568 void
569 vattr_null(struct vattr *vap)
570 {
571
572 vap->va_type = VNON;
573 vap->va_size = VNOVAL;
574 vap->va_bytes = VNOVAL;
575 vap->va_mode = VNOVAL;
576 vap->va_nlink = VNOVAL;
577 vap->va_uid = VNOVAL;
578 vap->va_gid = VNOVAL;
579 vap->va_fsid = VNOVAL;
580 vap->va_fileid = VNOVAL;
581 vap->va_blocksize = VNOVAL;
582 vap->va_rdev = VNOVAL;
583 vap->va_atime.tv_sec = VNOVAL;
584 vap->va_atime.tv_nsec = VNOVAL;
585 vap->va_mtime.tv_sec = VNOVAL;
586 vap->va_mtime.tv_nsec = VNOVAL;
587 vap->va_ctime.tv_sec = VNOVAL;
588 vap->va_ctime.tv_nsec = VNOVAL;
589 vap->va_birthtime.tv_sec = VNOVAL;
590 vap->va_birthtime.tv_nsec = VNOVAL;
591 vap->va_flags = VNOVAL;
592 vap->va_gen = VNOVAL;
593 vap->va_vaflags = 0;
594 }
595
596 /*
597 * This routine is called when we have too many vnodes. It attempts
598 * to free <count> vnodes and will potentially free vnodes that still
599 * have VM backing store (VM backing store is typically the cause
600 * of a vnode blowout so we want to do this). Therefore, this operation
601 * is not considered cheap.
602 *
603 * A number of conditions may prevent a vnode from being reclaimed.
604 * the buffer cache may have references on the vnode, a directory
605 * vnode may still have references due to the namei cache representing
606 * underlying files, or the vnode may be in active use. It is not
607 * desireable to reuse such vnodes. These conditions may cause the
608 * number of vnodes to reach some minimum value regardless of what
609 * you set kern.maxvnodes to. Do not set kern.maxvnodes too low.
610 */
611 static int
612 vlrureclaim(struct mount *mp)
613 {
614 struct vnode *vp;
615 int done;
616 int trigger;
617 int usevnodes;
618 int count;
619
620 /*
621 * Calculate the trigger point, don't allow user
622 * screwups to blow us up. This prevents us from
623 * recycling vnodes with lots of resident pages. We
624 * aren't trying to free memory, we are trying to
625 * free vnodes.
626 */
627 usevnodes = desiredvnodes;
628 if (usevnodes <= 0)
629 usevnodes = 1;
630 trigger = cnt.v_page_count * 2 / usevnodes;
631 done = 0;
632 vn_start_write(NULL, &mp, V_WAIT);
633 MNT_ILOCK(mp);
634 count = mp->mnt_nvnodelistsize / 10 + 1;
635 while (count != 0) {
636 vp = TAILQ_FIRST(&mp->mnt_nvnodelist);
637 while (vp != NULL && vp->v_type == VMARKER)
638 vp = TAILQ_NEXT(vp, v_nmntvnodes);
639 if (vp == NULL)
640 break;
641 TAILQ_REMOVE(&mp->mnt_nvnodelist, vp, v_nmntvnodes);
642 TAILQ_INSERT_TAIL(&mp->mnt_nvnodelist, vp, v_nmntvnodes);
643 --count;
644 if (!VI_TRYLOCK(vp))
645 goto next_iter;
646 /*
647 * If it's been deconstructed already, it's still
648 * referenced, or it exceeds the trigger, skip it.
649 */
650 if (vp->v_usecount ||
651 (!vlru_allow_cache_src &&
652 !LIST_EMPTY(&(vp)->v_cache_src)) ||
653 (vp->v_iflag & VI_DOOMED) != 0 || (vp->v_object != NULL &&
654 vp->v_object->resident_page_count > trigger)) {
655 VI_UNLOCK(vp);
656 goto next_iter;
657 }
658 MNT_IUNLOCK(mp);
659 vholdl(vp);
660 if (VOP_LOCK(vp, LK_INTERLOCK|LK_EXCLUSIVE|LK_NOWAIT)) {
661 vdrop(vp);
662 goto next_iter_mntunlocked;
663 }
664 VI_LOCK(vp);
665 /*
666 * v_usecount may have been bumped after VOP_LOCK() dropped
667 * the vnode interlock and before it was locked again.
668 *
669 * It is not necessary to recheck VI_DOOMED because it can
670 * only be set by another thread that holds both the vnode
671 * lock and vnode interlock. If another thread has the
672 * vnode lock before we get to VOP_LOCK() and obtains the
673 * vnode interlock after VOP_LOCK() drops the vnode
674 * interlock, the other thread will be unable to drop the
675 * vnode lock before our VOP_LOCK() call fails.
676 */
677 if (vp->v_usecount ||
678 (!vlru_allow_cache_src &&
679 !LIST_EMPTY(&(vp)->v_cache_src)) ||
680 (vp->v_object != NULL &&
681 vp->v_object->resident_page_count > trigger)) {
682 VOP_UNLOCK(vp, LK_INTERLOCK);
683 goto next_iter_mntunlocked;
684 }
685 KASSERT((vp->v_iflag & VI_DOOMED) == 0,
686 ("VI_DOOMED unexpectedly detected in vlrureclaim()"));
687 vgonel(vp);
688 VOP_UNLOCK(vp, 0);
689 vdropl(vp);
690 done++;
691 next_iter_mntunlocked:
692 if ((count % 256) != 0)
693 goto relock_mnt;
694 goto yield;
695 next_iter:
696 if ((count % 256) != 0)
697 continue;
698 MNT_IUNLOCK(mp);
699 yield:
700 uio_yield();
701 relock_mnt:
702 MNT_ILOCK(mp);
703 }
704 MNT_IUNLOCK(mp);
705 vn_finished_write(mp);
706 return done;
707 }
708
709 /*
710 * Attempt to keep the free list at wantfreevnodes length.
711 */
712 static void
713 vnlru_free(int count)
714 {
715 struct vnode *vp;
716 int vfslocked;
717
718 mtx_assert(&vnode_free_list_mtx, MA_OWNED);
719 for (; count > 0; count--) {
720 vp = TAILQ_FIRST(&vnode_free_list);
721 /*
722 * The list can be modified while the free_list_mtx
723 * has been dropped and vp could be NULL here.
724 */
725 if (!vp)
726 break;
727 VNASSERT(vp->v_op != NULL, vp,
728 ("vnlru_free: vnode already reclaimed."));
729 TAILQ_REMOVE(&vnode_free_list, vp, v_freelist);
730 /*
731 * Don't recycle if we can't get the interlock.
732 */
733 if (!VI_TRYLOCK(vp)) {
734 TAILQ_INSERT_TAIL(&vnode_free_list, vp, v_freelist);
735 continue;
736 }
737 VNASSERT(VCANRECYCLE(vp), vp,
738 ("vp inconsistent on freelist"));
739 freevnodes--;
740 vp->v_iflag &= ~VI_FREE;
741 vholdl(vp);
742 mtx_unlock(&vnode_free_list_mtx);
743 VI_UNLOCK(vp);
744 vfslocked = VFS_LOCK_GIANT(vp->v_mount);
745 vtryrecycle(vp);
746 VFS_UNLOCK_GIANT(vfslocked);
747 /*
748 * If the recycled succeeded this vdrop will actually free
749 * the vnode. If not it will simply place it back on
750 * the free list.
751 */
752 vdrop(vp);
753 mtx_lock(&vnode_free_list_mtx);
754 }
755 }
756 /*
757 * Attempt to recycle vnodes in a context that is always safe to block.
758 * Calling vlrurecycle() from the bowels of filesystem code has some
759 * interesting deadlock problems.
760 */
761 static struct proc *vnlruproc;
762 static int vnlruproc_sig;
763
764 static void
765 vnlru_proc(void)
766 {
767 struct mount *mp, *nmp;
768 int done, vfslocked;
769 struct proc *p = vnlruproc;
770
771 EVENTHANDLER_REGISTER(shutdown_pre_sync, kproc_shutdown, p,
772 SHUTDOWN_PRI_FIRST);
773
774 for (;;) {
775 kproc_suspend_check(p);
776 mtx_lock(&vnode_free_list_mtx);
777 if (freevnodes > wantfreevnodes)
778 vnlru_free(freevnodes - wantfreevnodes);
779 if (numvnodes <= desiredvnodes * 9 / 10) {
780 vnlruproc_sig = 0;
781 wakeup(&vnlruproc_sig);
782 msleep(vnlruproc, &vnode_free_list_mtx,
783 PVFS|PDROP, "vlruwt", hz);
784 continue;
785 }
786 mtx_unlock(&vnode_free_list_mtx);
787 done = 0;
788 mtx_lock(&mountlist_mtx);
789 for (mp = TAILQ_FIRST(&mountlist); mp != NULL; mp = nmp) {
790 if (vfs_busy(mp, MBF_NOWAIT | MBF_MNTLSTLOCK)) {
791 nmp = TAILQ_NEXT(mp, mnt_list);
792 continue;
793 }
794 vfslocked = VFS_LOCK_GIANT(mp);
795 done += vlrureclaim(mp);
796 VFS_UNLOCK_GIANT(vfslocked);
797 mtx_lock(&mountlist_mtx);
798 nmp = TAILQ_NEXT(mp, mnt_list);
799 vfs_unbusy(mp);
800 }
801 mtx_unlock(&mountlist_mtx);
802 if (done == 0) {
803 #if 0
804 /* These messages are temporary debugging aids */
805 if (vnlru_nowhere < 5)
806 printf("vnlru process getting nowhere..\n");
807 else if (vnlru_nowhere == 5)
808 printf("vnlru process messages stopped.\n");
809 #endif
810 vnlru_nowhere++;
811 tsleep(vnlruproc, PPAUSE, "vlrup", hz * 3);
812 } else
813 uio_yield();
814 }
815 }
816
817 static struct kproc_desc vnlru_kp = {
818 "vnlru",
819 vnlru_proc,
820 &vnlruproc
821 };
822 SYSINIT(vnlru, SI_SUB_KTHREAD_UPDATE, SI_ORDER_FIRST, kproc_start,
823 &vnlru_kp);
824
825 /*
826 * Routines having to do with the management of the vnode table.
827 */
828
829 void
830 vdestroy(struct vnode *vp)
831 {
832 struct bufobj *bo;
833
834 CTR2(KTR_VFS, "%s: vp %p", __func__, vp);
835 mtx_lock(&vnode_free_list_mtx);
836 numvnodes--;
837 mtx_unlock(&vnode_free_list_mtx);
838 bo = &vp->v_bufobj;
839 VNASSERT((vp->v_iflag & VI_FREE) == 0, vp,
840 ("cleaned vnode still on the free list."));
841 VNASSERT(vp->v_data == NULL, vp, ("cleaned vnode isn't"));
842 VNASSERT(vp->v_holdcnt == 0, vp, ("Non-zero hold count"));
843 VNASSERT(vp->v_usecount == 0, vp, ("Non-zero use count"));
844 VNASSERT(vp->v_writecount == 0, vp, ("Non-zero write count"));
845 VNASSERT(bo->bo_numoutput == 0, vp, ("Clean vnode has pending I/O's"));
846 VNASSERT(bo->bo_clean.bv_cnt == 0, vp, ("cleanbufcnt not 0"));
847 VNASSERT(bo->bo_clean.bv_root == NULL, vp, ("cleanblkroot not NULL"));
848 VNASSERT(bo->bo_dirty.bv_cnt == 0, vp, ("dirtybufcnt not 0"));
849 VNASSERT(bo->bo_dirty.bv_root == NULL, vp, ("dirtyblkroot not NULL"));
850 VNASSERT(TAILQ_EMPTY(&vp->v_cache_dst), vp, ("vp has namecache dst"));
851 VNASSERT(LIST_EMPTY(&vp->v_cache_src), vp, ("vp has namecache src"));
852 VNASSERT(vp->v_cache_dd == NULL, vp, ("vp has namecache for .."));
853 VI_UNLOCK(vp);
854 #ifdef MAC
855 mac_vnode_destroy(vp);
856 #endif
857 if (vp->v_pollinfo != NULL)
858 destroy_vpollinfo(vp->v_pollinfo);
859 #ifdef INVARIANTS
860 /* XXX Elsewhere we can detect an already freed vnode via NULL v_op. */
861 vp->v_op = NULL;
862 #endif
863 lockdestroy(vp->v_vnlock);
864 mtx_destroy(&vp->v_interlock);
865 mtx_destroy(BO_MTX(bo));
866 uma_zfree(vnode_zone, vp);
867 }
868
869 /*
870 * Try to recycle a freed vnode. We abort if anyone picks up a reference
871 * before we actually vgone(). This function must be called with the vnode
872 * held to prevent the vnode from being returned to the free list midway
873 * through vgone().
874 */
875 static int
876 vtryrecycle(struct vnode *vp)
877 {
878 struct mount *vnmp;
879
880 CTR2(KTR_VFS, "%s: vp %p", __func__, vp);
881 VNASSERT(vp->v_holdcnt, vp,
882 ("vtryrecycle: Recycling vp %p without a reference.", vp));
883 /*
884 * This vnode may found and locked via some other list, if so we
885 * can't recycle it yet.
886 */
887 if (VOP_LOCK(vp, LK_EXCLUSIVE | LK_NOWAIT) != 0) {
888 CTR2(KTR_VFS,
889 "%s: impossible to recycle, vp %p lock is already held",
890 __func__, vp);
891 return (EWOULDBLOCK);
892 }
893 /*
894 * Don't recycle if its filesystem is being suspended.
895 */
896 if (vn_start_write(vp, &vnmp, V_NOWAIT) != 0) {
897 VOP_UNLOCK(vp, 0);
898 CTR2(KTR_VFS,
899 "%s: impossible to recycle, cannot start the write for %p",
900 __func__, vp);
901 return (EBUSY);
902 }
903 /*
904 * If we got this far, we need to acquire the interlock and see if
905 * anyone picked up this vnode from another list. If not, we will
906 * mark it with DOOMED via vgonel() so that anyone who does find it
907 * will skip over it.
908 */
909 VI_LOCK(vp);
910 if (vp->v_usecount) {
911 VOP_UNLOCK(vp, LK_INTERLOCK);
912 vn_finished_write(vnmp);
913 CTR2(KTR_VFS,
914 "%s: impossible to recycle, %p is already referenced",
915 __func__, vp);
916 return (EBUSY);
917 }
918 if ((vp->v_iflag & VI_DOOMED) == 0)
919 vgonel(vp);
920 VOP_UNLOCK(vp, LK_INTERLOCK);
921 vn_finished_write(vnmp);
922 return (0);
923 }
924
925 /*
926 * Return the next vnode from the free list.
927 */
928 int
929 getnewvnode(const char *tag, struct mount *mp, struct vop_vector *vops,
930 struct vnode **vpp)
931 {
932 struct vnode *vp = NULL;
933 struct bufobj *bo;
934
935 CTR3(KTR_VFS, "%s: mp %p with tag %s", __func__, mp, tag);
936 mtx_lock(&vnode_free_list_mtx);
937 /*
938 * Lend our context to reclaim vnodes if they've exceeded the max.
939 */
940 if (freevnodes > wantfreevnodes)
941 vnlru_free(1);
942 /*
943 * Wait for available vnodes.
944 */
945 if (numvnodes > desiredvnodes) {
946 if (mp != NULL && (mp->mnt_kern_flag & MNTK_SUSPEND)) {
947 /*
948 * File system is beeing suspended, we cannot risk a
949 * deadlock here, so allocate new vnode anyway.
950 */
951 if (freevnodes > wantfreevnodes)
952 vnlru_free(freevnodes - wantfreevnodes);
953 goto alloc;
954 }
955 if (vnlruproc_sig == 0) {
956 vnlruproc_sig = 1; /* avoid unnecessary wakeups */
957 wakeup(vnlruproc);
958 }
959 msleep(&vnlruproc_sig, &vnode_free_list_mtx, PVFS,
960 "vlruwk", hz);
961 #if 0 /* XXX Not all VFS_VGET/ffs_vget callers check returns. */
962 if (numvnodes > desiredvnodes) {
963 mtx_unlock(&vnode_free_list_mtx);
964 return (ENFILE);
965 }
966 #endif
967 }
968 alloc:
969 numvnodes++;
970 mtx_unlock(&vnode_free_list_mtx);
971 vp = (struct vnode *) uma_zalloc(vnode_zone, M_WAITOK|M_ZERO);
972 /*
973 * Setup locks.
974 */
975 vp->v_vnlock = &vp->v_lock;
976 mtx_init(&vp->v_interlock, "vnode interlock", NULL, MTX_DEF);
977 /*
978 * By default, don't allow shared locks unless filesystems
979 * opt-in.
980 */
981 lockinit(vp->v_vnlock, PVFS, tag, VLKTIMEOUT, LK_NOSHARE);
982 /*
983 * Initialize bufobj.
984 */
985 bo = &vp->v_bufobj;
986 bo->__bo_vnode = vp;
987 mtx_init(BO_MTX(bo), "bufobj interlock", NULL, MTX_DEF);
988 bo->bo_ops = &buf_ops_bio;
989 bo->bo_private = vp;
990 TAILQ_INIT(&bo->bo_clean.bv_hd);
991 TAILQ_INIT(&bo->bo_dirty.bv_hd);
992 /*
993 * Initialize namecache.
994 */
995 LIST_INIT(&vp->v_cache_src);
996 TAILQ_INIT(&vp->v_cache_dst);
997 /*
998 * Finalize various vnode identity bits.
999 */
1000 vp->v_type = VNON;
1001 vp->v_tag = tag;
1002 vp->v_op = vops;
1003 v_incr_usecount(vp);
1004 vp->v_data = 0;
1005 #ifdef MAC
1006 mac_vnode_init(vp);
1007 if (mp != NULL && (mp->mnt_flag & MNT_MULTILABEL) == 0)
1008 mac_vnode_associate_singlelabel(mp, vp);
1009 else if (mp == NULL && vops != &dead_vnodeops)
1010 printf("NULL mp in getnewvnode()\n");
1011 #endif
1012 if (mp != NULL) {
1013 bo->bo_bsize = mp->mnt_stat.f_iosize;
1014 if ((mp->mnt_kern_flag & MNTK_NOKNOTE) != 0)
1015 vp->v_vflag |= VV_NOKNOTE;
1016 }
1017
1018 *vpp = vp;
1019 return (0);
1020 }
1021
1022 /*
1023 * Delete from old mount point vnode list, if on one.
1024 */
1025 static void
1026 delmntque(struct vnode *vp)
1027 {
1028 struct mount *mp;
1029
1030 mp = vp->v_mount;
1031 if (mp == NULL)
1032 return;
1033 MNT_ILOCK(mp);
1034 vp->v_mount = NULL;
1035 VNASSERT(mp->mnt_nvnodelistsize > 0, vp,
1036 ("bad mount point vnode list size"));
1037 TAILQ_REMOVE(&mp->mnt_nvnodelist, vp, v_nmntvnodes);
1038 mp->mnt_nvnodelistsize--;
1039 MNT_REL(mp);
1040 MNT_IUNLOCK(mp);
1041 }
1042
1043 static void
1044 insmntque_stddtr(struct vnode *vp, void *dtr_arg)
1045 {
1046
1047 vp->v_data = NULL;
1048 vp->v_op = &dead_vnodeops;
1049 /* XXX non mp-safe fs may still call insmntque with vnode
1050 unlocked */
1051 if (!VOP_ISLOCKED(vp))
1052 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
1053 vgone(vp);
1054 vput(vp);
1055 }
1056
1057 /*
1058 * Insert into list of vnodes for the new mount point, if available.
1059 */
1060 int
1061 insmntque1(struct vnode *vp, struct mount *mp,
1062 void (*dtr)(struct vnode *, void *), void *dtr_arg)
1063 {
1064 int locked;
1065
1066 KASSERT(vp->v_mount == NULL,
1067 ("insmntque: vnode already on per mount vnode list"));
1068 VNASSERT(mp != NULL, vp, ("Don't call insmntque(foo, NULL)"));
1069 #ifdef DEBUG_VFS_LOCKS
1070 if (!VFS_NEEDSGIANT(mp))
1071 ASSERT_VOP_ELOCKED(vp,
1072 "insmntque: mp-safe fs and non-locked vp");
1073 #endif
1074 MNT_ILOCK(mp);
1075 if ((mp->mnt_kern_flag & MNTK_NOINSMNTQ) != 0 &&
1076 ((mp->mnt_kern_flag & MNTK_UNMOUNTF) != 0 ||
1077 mp->mnt_nvnodelistsize == 0)) {
1078 locked = VOP_ISLOCKED(vp);
1079 if (!locked || (locked == LK_EXCLUSIVE &&
1080 (vp->v_vflag & VV_FORCEINSMQ) == 0)) {
1081 MNT_IUNLOCK(mp);
1082 if (dtr != NULL)
1083 dtr(vp, dtr_arg);
1084 return (EBUSY);
1085 }
1086 }
1087 vp->v_mount = mp;
1088 MNT_REF(mp);
1089 TAILQ_INSERT_TAIL(&mp->mnt_nvnodelist, vp, v_nmntvnodes);
1090 VNASSERT(mp->mnt_nvnodelistsize >= 0, vp,
1091 ("neg mount point vnode list size"));
1092 mp->mnt_nvnodelistsize++;
1093 MNT_IUNLOCK(mp);
1094 return (0);
1095 }
1096
1097 int
1098 insmntque(struct vnode *vp, struct mount *mp)
1099 {
1100
1101 return (insmntque1(vp, mp, insmntque_stddtr, NULL));
1102 }
1103
1104 /*
1105 * Flush out and invalidate all buffers associated with a bufobj
1106 * Called with the underlying object locked.
1107 */
1108 int
1109 bufobj_invalbuf(struct bufobj *bo, int flags, int slpflag, int slptimeo)
1110 {
1111 int error;
1112
1113 BO_LOCK(bo);
1114 if (flags & V_SAVE) {
1115 error = bufobj_wwait(bo, slpflag, slptimeo);
1116 if (error) {
1117 BO_UNLOCK(bo);
1118 return (error);
1119 }
1120 if (bo->bo_dirty.bv_cnt > 0) {
1121 BO_UNLOCK(bo);
1122 if ((error = BO_SYNC(bo, MNT_WAIT)) != 0)
1123 return (error);
1124 /*
1125 * XXX We could save a lock/unlock if this was only
1126 * enabled under INVARIANTS
1127 */
1128 BO_LOCK(bo);
1129 if (bo->bo_numoutput > 0 || bo->bo_dirty.bv_cnt > 0)
1130 panic("vinvalbuf: dirty bufs");
1131 }
1132 }
1133 /*
1134 * If you alter this loop please notice that interlock is dropped and
1135 * reacquired in flushbuflist. Special care is needed to ensure that
1136 * no race conditions occur from this.
1137 */
1138 do {
1139 error = flushbuflist(&bo->bo_clean,
1140 flags, bo, slpflag, slptimeo);
1141 if (error == 0)
1142 error = flushbuflist(&bo->bo_dirty,
1143 flags, bo, slpflag, slptimeo);
1144 if (error != 0 && error != EAGAIN) {
1145 BO_UNLOCK(bo);
1146 return (error);
1147 }
1148 } while (error != 0);
1149
1150 /*
1151 * Wait for I/O to complete. XXX needs cleaning up. The vnode can
1152 * have write I/O in-progress but if there is a VM object then the
1153 * VM object can also have read-I/O in-progress.
1154 */
1155 do {
1156 bufobj_wwait(bo, 0, 0);
1157 BO_UNLOCK(bo);
1158 if (bo->bo_object != NULL) {
1159 VM_OBJECT_LOCK(bo->bo_object);
1160 vm_object_pip_wait(bo->bo_object, "bovlbx");
1161 VM_OBJECT_UNLOCK(bo->bo_object);
1162 }
1163 BO_LOCK(bo);
1164 } while (bo->bo_numoutput > 0);
1165 BO_UNLOCK(bo);
1166
1167 /*
1168 * Destroy the copy in the VM cache, too.
1169 */
1170 if (bo->bo_object != NULL && (flags & (V_ALT | V_NORMAL)) == 0) {
1171 VM_OBJECT_LOCK(bo->bo_object);
1172 vm_object_page_remove(bo->bo_object, 0, 0,
1173 (flags & V_SAVE) ? TRUE : FALSE);
1174 VM_OBJECT_UNLOCK(bo->bo_object);
1175 }
1176
1177 #ifdef INVARIANTS
1178 BO_LOCK(bo);
1179 if ((flags & (V_ALT | V_NORMAL)) == 0 &&
1180 (bo->bo_dirty.bv_cnt > 0 || bo->bo_clean.bv_cnt > 0))
1181 panic("vinvalbuf: flush failed");
1182 BO_UNLOCK(bo);
1183 #endif
1184 return (0);
1185 }
1186
1187 /*
1188 * Flush out and invalidate all buffers associated with a vnode.
1189 * Called with the underlying object locked.
1190 */
1191 int
1192 vinvalbuf(struct vnode *vp, int flags, int slpflag, int slptimeo)
1193 {
1194
1195 CTR3(KTR_VFS, "%s: vp %p with flags %d", __func__, vp, flags);
1196 ASSERT_VOP_LOCKED(vp, "vinvalbuf");
1197 return (bufobj_invalbuf(&vp->v_bufobj, flags, slpflag, slptimeo));
1198 }
1199
1200 /*
1201 * Flush out buffers on the specified list.
1202 *
1203 */
1204 static int
1205 flushbuflist( struct bufv *bufv, int flags, struct bufobj *bo, int slpflag,
1206 int slptimeo)
1207 {
1208 struct buf *bp, *nbp;
1209 int retval, error;
1210 daddr_t lblkno;
1211 b_xflags_t xflags;
1212
1213 ASSERT_BO_LOCKED(bo);
1214
1215 retval = 0;
1216 TAILQ_FOREACH_SAFE(bp, &bufv->bv_hd, b_bobufs, nbp) {
1217 if (((flags & V_NORMAL) && (bp->b_xflags & BX_ALTDATA)) ||
1218 ((flags & V_ALT) && (bp->b_xflags & BX_ALTDATA) == 0)) {
1219 continue;
1220 }
1221 lblkno = 0;
1222 xflags = 0;
1223 if (nbp != NULL) {
1224 lblkno = nbp->b_lblkno;
1225 xflags = nbp->b_xflags &
1226 (BX_BKGRDMARKER | BX_VNDIRTY | BX_VNCLEAN);
1227 }
1228 retval = EAGAIN;
1229 error = BUF_TIMELOCK(bp,
1230 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK, BO_MTX(bo),
1231 "flushbuf", slpflag, slptimeo);
1232 if (error) {
1233 BO_LOCK(bo);
1234 return (error != ENOLCK ? error : EAGAIN);
1235 }
1236 KASSERT(bp->b_bufobj == bo,
1237 ("bp %p wrong b_bufobj %p should be %p",
1238 bp, bp->b_bufobj, bo));
1239 if (bp->b_bufobj != bo) { /* XXX: necessary ? */
1240 BUF_UNLOCK(bp);
1241 BO_LOCK(bo);
1242 return (EAGAIN);
1243 }
1244 /*
1245 * XXX Since there are no node locks for NFS, I
1246 * believe there is a slight chance that a delayed
1247 * write will occur while sleeping just above, so
1248 * check for it.
1249 */
1250 if (((bp->b_flags & (B_DELWRI | B_INVAL)) == B_DELWRI) &&
1251 (flags & V_SAVE)) {
1252 bremfree(bp);
1253 bp->b_flags |= B_ASYNC;
1254 bwrite(bp);
1255 BO_LOCK(bo);
1256 return (EAGAIN); /* XXX: why not loop ? */
1257 }
1258 bremfree(bp);
1259 bp->b_flags |= (B_INVAL | B_RELBUF);
1260 bp->b_flags &= ~B_ASYNC;
1261 brelse(bp);
1262 BO_LOCK(bo);
1263 if (nbp != NULL &&
1264 (nbp->b_bufobj != bo ||
1265 nbp->b_lblkno != lblkno ||
1266 (nbp->b_xflags &
1267 (BX_BKGRDMARKER | BX_VNDIRTY | BX_VNCLEAN)) != xflags))
1268 break; /* nbp invalid */
1269 }
1270 return (retval);
1271 }
1272
1273 /*
1274 * Truncate a file's buffer and pages to a specified length. This
1275 * is in lieu of the old vinvalbuf mechanism, which performed unneeded
1276 * sync activity.
1277 */
1278 int
1279 vtruncbuf(struct vnode *vp, struct ucred *cred, struct thread *td,
1280 off_t length, int blksize)
1281 {
1282 struct buf *bp, *nbp;
1283 int anyfreed;
1284 int trunclbn;
1285 struct bufobj *bo;
1286
1287 CTR5(KTR_VFS, "%s: vp %p with cred %p and block %d:%ju", __func__,
1288 vp, cred, blksize, (uintmax_t)length);
1289
1290 /*
1291 * Round up to the *next* lbn.
1292 */
1293 trunclbn = (length + blksize - 1) / blksize;
1294
1295 ASSERT_VOP_LOCKED(vp, "vtruncbuf");
1296 restart:
1297 bo = &vp->v_bufobj;
1298 BO_LOCK(bo);
1299 anyfreed = 1;
1300 for (;anyfreed;) {
1301 anyfreed = 0;
1302 TAILQ_FOREACH_SAFE(bp, &bo->bo_clean.bv_hd, b_bobufs, nbp) {
1303 if (bp->b_lblkno < trunclbn)
1304 continue;
1305 if (BUF_LOCK(bp,
1306 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK,
1307 BO_MTX(bo)) == ENOLCK)
1308 goto restart;
1309
1310 bremfree(bp);
1311 bp->b_flags |= (B_INVAL | B_RELBUF);
1312 bp->b_flags &= ~B_ASYNC;
1313 brelse(bp);
1314 anyfreed = 1;
1315
1316 if (nbp != NULL &&
1317 (((nbp->b_xflags & BX_VNCLEAN) == 0) ||
1318 (nbp->b_vp != vp) ||
1319 (nbp->b_flags & B_DELWRI))) {
1320 goto restart;
1321 }
1322 BO_LOCK(bo);
1323 }
1324
1325 TAILQ_FOREACH_SAFE(bp, &bo->bo_dirty.bv_hd, b_bobufs, nbp) {
1326 if (bp->b_lblkno < trunclbn)
1327 continue;
1328 if (BUF_LOCK(bp,
1329 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK,
1330 BO_MTX(bo)) == ENOLCK)
1331 goto restart;
1332 bremfree(bp);
1333 bp->b_flags |= (B_INVAL | B_RELBUF);
1334 bp->b_flags &= ~B_ASYNC;
1335 brelse(bp);
1336 anyfreed = 1;
1337 if (nbp != NULL &&
1338 (((nbp->b_xflags & BX_VNDIRTY) == 0) ||
1339 (nbp->b_vp != vp) ||
1340 (nbp->b_flags & B_DELWRI) == 0)) {
1341 goto restart;
1342 }
1343 BO_LOCK(bo);
1344 }
1345 }
1346
1347 if (length > 0) {
1348 restartsync:
1349 TAILQ_FOREACH_SAFE(bp, &bo->bo_dirty.bv_hd, b_bobufs, nbp) {
1350 if (bp->b_lblkno > 0)
1351 continue;
1352 /*
1353 * Since we hold the vnode lock this should only
1354 * fail if we're racing with the buf daemon.
1355 */
1356 if (BUF_LOCK(bp,
1357 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK,
1358 BO_MTX(bo)) == ENOLCK) {
1359 goto restart;
1360 }
1361 VNASSERT((bp->b_flags & B_DELWRI), vp,
1362 ("buf(%p) on dirty queue without DELWRI", bp));
1363
1364 bremfree(bp);
1365 bawrite(bp);
1366 BO_LOCK(bo);
1367 goto restartsync;
1368 }
1369 }
1370
1371 bufobj_wwait(bo, 0, 0);
1372 BO_UNLOCK(bo);
1373 vnode_pager_setsize(vp, length);
1374
1375 return (0);
1376 }
1377
1378 /*
1379 * buf_splay() - splay tree core for the clean/dirty list of buffers in
1380 * a vnode.
1381 *
1382 * NOTE: We have to deal with the special case of a background bitmap
1383 * buffer, a situation where two buffers will have the same logical
1384 * block offset. We want (1) only the foreground buffer to be accessed
1385 * in a lookup and (2) must differentiate between the foreground and
1386 * background buffer in the splay tree algorithm because the splay
1387 * tree cannot normally handle multiple entities with the same 'index'.
1388 * We accomplish this by adding differentiating flags to the splay tree's
1389 * numerical domain.
1390 */
1391 static
1392 struct buf *
1393 buf_splay(daddr_t lblkno, b_xflags_t xflags, struct buf *root)
1394 {
1395 struct buf dummy;
1396 struct buf *lefttreemax, *righttreemin, *y;
1397
1398 if (root == NULL)
1399 return (NULL);
1400 lefttreemax = righttreemin = &dummy;
1401 for (;;) {
1402 if (lblkno < root->b_lblkno ||
1403 (lblkno == root->b_lblkno &&
1404 (xflags & BX_BKGRDMARKER) < (root->b_xflags & BX_BKGRDMARKER))) {
1405 if ((y = root->b_left) == NULL)
1406 break;
1407 if (lblkno < y->b_lblkno) {
1408 /* Rotate right. */
1409 root->b_left = y->b_right;
1410 y->b_right = root;
1411 root = y;
1412 if ((y = root->b_left) == NULL)
1413 break;
1414 }
1415 /* Link into the new root's right tree. */
1416 righttreemin->b_left = root;
1417 righttreemin = root;
1418 } else if (lblkno > root->b_lblkno ||
1419 (lblkno == root->b_lblkno &&
1420 (xflags & BX_BKGRDMARKER) > (root->b_xflags & BX_BKGRDMARKER))) {
1421 if ((y = root->b_right) == NULL)
1422 break;
1423 if (lblkno > y->b_lblkno) {
1424 /* Rotate left. */
1425 root->b_right = y->b_left;
1426 y->b_left = root;
1427 root = y;
1428 if ((y = root->b_right) == NULL)
1429 break;
1430 }
1431 /* Link into the new root's left tree. */
1432 lefttreemax->b_right = root;
1433 lefttreemax = root;
1434 } else {
1435 break;
1436 }
1437 root = y;
1438 }
1439 /* Assemble the new root. */
1440 lefttreemax->b_right = root->b_left;
1441 righttreemin->b_left = root->b_right;
1442 root->b_left = dummy.b_right;
1443 root->b_right = dummy.b_left;
1444 return (root);
1445 }
1446
1447 static void
1448 buf_vlist_remove(struct buf *bp)
1449 {
1450 struct buf *root;
1451 struct bufv *bv;
1452
1453 KASSERT(bp->b_bufobj != NULL, ("No b_bufobj %p", bp));
1454 ASSERT_BO_LOCKED(bp->b_bufobj);
1455 KASSERT((bp->b_xflags & (BX_VNDIRTY|BX_VNCLEAN)) !=
1456 (BX_VNDIRTY|BX_VNCLEAN),
1457 ("buf_vlist_remove: Buf %p is on two lists", bp));
1458 if (bp->b_xflags & BX_VNDIRTY)
1459 bv = &bp->b_bufobj->bo_dirty;
1460 else
1461 bv = &bp->b_bufobj->bo_clean;
1462 if (bp != bv->bv_root) {
1463 root = buf_splay(bp->b_lblkno, bp->b_xflags, bv->bv_root);
1464 KASSERT(root == bp, ("splay lookup failed in remove"));
1465 }
1466 if (bp->b_left == NULL) {
1467 root = bp->b_right;
1468 } else {
1469 root = buf_splay(bp->b_lblkno, bp->b_xflags, bp->b_left);
1470 root->b_right = bp->b_right;
1471 }
1472 bv->bv_root = root;
1473 TAILQ_REMOVE(&bv->bv_hd, bp, b_bobufs);
1474 bv->bv_cnt--;
1475 bp->b_xflags &= ~(BX_VNDIRTY | BX_VNCLEAN);
1476 }
1477
1478 /*
1479 * Add the buffer to the sorted clean or dirty block list using a
1480 * splay tree algorithm.
1481 *
1482 * NOTE: xflags is passed as a constant, optimizing this inline function!
1483 */
1484 static void
1485 buf_vlist_add(struct buf *bp, struct bufobj *bo, b_xflags_t xflags)
1486 {
1487 struct buf *root;
1488 struct bufv *bv;
1489
1490 ASSERT_BO_LOCKED(bo);
1491 KASSERT((bp->b_xflags & (BX_VNDIRTY|BX_VNCLEAN)) == 0,
1492 ("buf_vlist_add: Buf %p has existing xflags %d", bp, bp->b_xflags));
1493 bp->b_xflags |= xflags;
1494 if (xflags & BX_VNDIRTY)
1495 bv = &bo->bo_dirty;
1496 else
1497 bv = &bo->bo_clean;
1498
1499 root = buf_splay(bp->b_lblkno, bp->b_xflags, bv->bv_root);
1500 if (root == NULL) {
1501 bp->b_left = NULL;
1502 bp->b_right = NULL;
1503 TAILQ_INSERT_TAIL(&bv->bv_hd, bp, b_bobufs);
1504 } else if (bp->b_lblkno < root->b_lblkno ||
1505 (bp->b_lblkno == root->b_lblkno &&
1506 (bp->b_xflags & BX_BKGRDMARKER) < (root->b_xflags & BX_BKGRDMARKER))) {
1507 bp->b_left = root->b_left;
1508 bp->b_right = root;
1509 root->b_left = NULL;
1510 TAILQ_INSERT_BEFORE(root, bp, b_bobufs);
1511 } else {
1512 bp->b_right = root->b_right;
1513 bp->b_left = root;
1514 root->b_right = NULL;
1515 TAILQ_INSERT_AFTER(&bv->bv_hd, root, bp, b_bobufs);
1516 }
1517 bv->bv_cnt++;
1518 bv->bv_root = bp;
1519 }
1520
1521 /*
1522 * Lookup a buffer using the splay tree. Note that we specifically avoid
1523 * shadow buffers used in background bitmap writes.
1524 *
1525 * This code isn't quite efficient as it could be because we are maintaining
1526 * two sorted lists and do not know which list the block resides in.
1527 *
1528 * During a "make buildworld" the desired buffer is found at one of
1529 * the roots more than 60% of the time. Thus, checking both roots
1530 * before performing either splay eliminates unnecessary splays on the
1531 * first tree splayed.
1532 */
1533 struct buf *
1534 gbincore(struct bufobj *bo, daddr_t lblkno)
1535 {
1536 struct buf *bp;
1537
1538 ASSERT_BO_LOCKED(bo);
1539 if ((bp = bo->bo_clean.bv_root) != NULL &&
1540 bp->b_lblkno == lblkno && !(bp->b_xflags & BX_BKGRDMARKER))
1541 return (bp);
1542 if ((bp = bo->bo_dirty.bv_root) != NULL &&
1543 bp->b_lblkno == lblkno && !(bp->b_xflags & BX_BKGRDMARKER))
1544 return (bp);
1545 if ((bp = bo->bo_clean.bv_root) != NULL) {
1546 bo->bo_clean.bv_root = bp = buf_splay(lblkno, 0, bp);
1547 if (bp->b_lblkno == lblkno && !(bp->b_xflags & BX_BKGRDMARKER))
1548 return (bp);
1549 }
1550 if ((bp = bo->bo_dirty.bv_root) != NULL) {
1551 bo->bo_dirty.bv_root = bp = buf_splay(lblkno, 0, bp);
1552 if (bp->b_lblkno == lblkno && !(bp->b_xflags & BX_BKGRDMARKER))
1553 return (bp);
1554 }
1555 return (NULL);
1556 }
1557
1558 /*
1559 * Associate a buffer with a vnode.
1560 */
1561 void
1562 bgetvp(struct vnode *vp, struct buf *bp)
1563 {
1564 struct bufobj *bo;
1565
1566 bo = &vp->v_bufobj;
1567 ASSERT_BO_LOCKED(bo);
1568 VNASSERT(bp->b_vp == NULL, bp->b_vp, ("bgetvp: not free"));
1569
1570 CTR3(KTR_BUF, "bgetvp(%p) vp %p flags %X", bp, vp, bp->b_flags);
1571 VNASSERT((bp->b_xflags & (BX_VNDIRTY|BX_VNCLEAN)) == 0, vp,
1572 ("bgetvp: bp already attached! %p", bp));
1573
1574 vhold(vp);
1575 if (VFS_NEEDSGIANT(vp->v_mount) || bo->bo_flag & BO_NEEDSGIANT)
1576 bp->b_flags |= B_NEEDSGIANT;
1577 bp->b_vp = vp;
1578 bp->b_bufobj = bo;
1579 /*
1580 * Insert onto list for new vnode.
1581 */
1582 buf_vlist_add(bp, bo, BX_VNCLEAN);
1583 }
1584
1585 /*
1586 * Disassociate a buffer from a vnode.
1587 */
1588 void
1589 brelvp(struct buf *bp)
1590 {
1591 struct bufobj *bo;
1592 struct vnode *vp;
1593
1594 CTR3(KTR_BUF, "brelvp(%p) vp %p flags %X", bp, bp->b_vp, bp->b_flags);
1595 KASSERT(bp->b_vp != NULL, ("brelvp: NULL"));
1596
1597 /*
1598 * Delete from old vnode list, if on one.
1599 */
1600 vp = bp->b_vp; /* XXX */
1601 bo = bp->b_bufobj;
1602 BO_LOCK(bo);
1603 if (bp->b_xflags & (BX_VNDIRTY | BX_VNCLEAN))
1604 buf_vlist_remove(bp);
1605 else
1606 panic("brelvp: Buffer %p not on queue.", bp);
1607 if ((bo->bo_flag & BO_ONWORKLST) && bo->bo_dirty.bv_cnt == 0) {
1608 bo->bo_flag &= ~BO_ONWORKLST;
1609 mtx_lock(&sync_mtx);
1610 LIST_REMOVE(bo, bo_synclist);
1611 syncer_worklist_len--;
1612 mtx_unlock(&sync_mtx);
1613 }
1614 bp->b_flags &= ~B_NEEDSGIANT;
1615 bp->b_vp = NULL;
1616 bp->b_bufobj = NULL;
1617 BO_UNLOCK(bo);
1618 vdrop(vp);
1619 }
1620
1621 /*
1622 * Add an item to the syncer work queue.
1623 */
1624 static void
1625 vn_syncer_add_to_worklist(struct bufobj *bo, int delay)
1626 {
1627 int queue, slot;
1628
1629 ASSERT_BO_LOCKED(bo);
1630
1631 mtx_lock(&sync_mtx);
1632 if (bo->bo_flag & BO_ONWORKLST)
1633 LIST_REMOVE(bo, bo_synclist);
1634 else {
1635 bo->bo_flag |= BO_ONWORKLST;
1636 syncer_worklist_len++;
1637 }
1638
1639 if (delay > syncer_maxdelay - 2)
1640 delay = syncer_maxdelay - 2;
1641 slot = (syncer_delayno + delay) & syncer_mask;
1642
1643 queue = VFS_NEEDSGIANT(bo->__bo_vnode->v_mount) ? WI_GIANTQ :
1644 WI_MPSAFEQ;
1645 LIST_INSERT_HEAD(&syncer_workitem_pending[queue][slot], bo,
1646 bo_synclist);
1647 mtx_unlock(&sync_mtx);
1648 }
1649
1650 static int
1651 sysctl_vfs_worklist_len(SYSCTL_HANDLER_ARGS)
1652 {
1653 int error, len;
1654
1655 mtx_lock(&sync_mtx);
1656 len = syncer_worklist_len - sync_vnode_count;
1657 mtx_unlock(&sync_mtx);
1658 error = SYSCTL_OUT(req, &len, sizeof(len));
1659 return (error);
1660 }
1661
1662 SYSCTL_PROC(_vfs, OID_AUTO, worklist_len, CTLTYPE_INT | CTLFLAG_RD, NULL, 0,
1663 sysctl_vfs_worklist_len, "I", "Syncer thread worklist length");
1664
1665 static struct proc *updateproc;
1666 static void sched_sync(void);
1667 static struct kproc_desc up_kp = {
1668 "syncer",
1669 sched_sync,
1670 &updateproc
1671 };
1672 SYSINIT(syncer, SI_SUB_KTHREAD_UPDATE, SI_ORDER_FIRST, kproc_start, &up_kp);
1673
1674 static int
1675 sync_vnode(struct synclist *slp, struct bufobj **bo, struct thread *td)
1676 {
1677 struct vnode *vp;
1678 struct mount *mp;
1679
1680 *bo = LIST_FIRST(slp);
1681 if (*bo == NULL)
1682 return (0);
1683 vp = (*bo)->__bo_vnode; /* XXX */
1684 if (VOP_ISLOCKED(vp) != 0 || VI_TRYLOCK(vp) == 0)
1685 return (1);
1686 /*
1687 * We use vhold in case the vnode does not
1688 * successfully sync. vhold prevents the vnode from
1689 * going away when we unlock the sync_mtx so that
1690 * we can acquire the vnode interlock.
1691 */
1692 vholdl(vp);
1693 mtx_unlock(&sync_mtx);
1694 VI_UNLOCK(vp);
1695 if (vn_start_write(vp, &mp, V_NOWAIT) != 0) {
1696 vdrop(vp);
1697 mtx_lock(&sync_mtx);
1698 return (*bo == LIST_FIRST(slp));
1699 }
1700 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
1701 (void) VOP_FSYNC(vp, MNT_LAZY, td);
1702 VOP_UNLOCK(vp, 0);
1703 vn_finished_write(mp);
1704 BO_LOCK(*bo);
1705 if (((*bo)->bo_flag & BO_ONWORKLST) != 0) {
1706 /*
1707 * Put us back on the worklist. The worklist
1708 * routine will remove us from our current
1709 * position and then add us back in at a later
1710 * position.
1711 */
1712 vn_syncer_add_to_worklist(*bo, syncdelay);
1713 }
1714 BO_UNLOCK(*bo);
1715 vdrop(vp);
1716 mtx_lock(&sync_mtx);
1717 return (0);
1718 }
1719
1720 /*
1721 * System filesystem synchronizer daemon.
1722 */
1723 static void
1724 sched_sync(void)
1725 {
1726 struct synclist *gnext, *next;
1727 struct synclist *gslp, *slp;
1728 struct bufobj *bo;
1729 long starttime;
1730 struct thread *td = curthread;
1731 int last_work_seen;
1732 int net_worklist_len;
1733 int syncer_final_iter;
1734 int first_printf;
1735 int error;
1736
1737 last_work_seen = 0;
1738 syncer_final_iter = 0;
1739 first_printf = 1;
1740 syncer_state = SYNCER_RUNNING;
1741 starttime = time_uptime;
1742 td->td_pflags |= TDP_NORUNNINGBUF;
1743
1744 EVENTHANDLER_REGISTER(shutdown_pre_sync, syncer_shutdown, td->td_proc,
1745 SHUTDOWN_PRI_LAST);
1746
1747 mtx_lock(&sync_mtx);
1748 for (;;) {
1749 if (syncer_state == SYNCER_FINAL_DELAY &&
1750 syncer_final_iter == 0) {
1751 mtx_unlock(&sync_mtx);
1752 kproc_suspend_check(td->td_proc);
1753 mtx_lock(&sync_mtx);
1754 }
1755 net_worklist_len = syncer_worklist_len - sync_vnode_count;
1756 if (syncer_state != SYNCER_RUNNING &&
1757 starttime != time_uptime) {
1758 if (first_printf) {
1759 printf("\nSyncing disks, vnodes remaining...");
1760 first_printf = 0;
1761 }
1762 printf("%d ", net_worklist_len);
1763 }
1764 starttime = time_uptime;
1765
1766 /*
1767 * Push files whose dirty time has expired. Be careful
1768 * of interrupt race on slp queue.
1769 *
1770 * Skip over empty worklist slots when shutting down.
1771 */
1772 do {
1773 slp = &syncer_workitem_pending[WI_MPSAFEQ][syncer_delayno];
1774 gslp = &syncer_workitem_pending[WI_GIANTQ][syncer_delayno];
1775 syncer_delayno += 1;
1776 if (syncer_delayno == syncer_maxdelay)
1777 syncer_delayno = 0;
1778 next = &syncer_workitem_pending[WI_MPSAFEQ][syncer_delayno];
1779 gnext = &syncer_workitem_pending[WI_GIANTQ][syncer_delayno];
1780 /*
1781 * If the worklist has wrapped since the
1782 * it was emptied of all but syncer vnodes,
1783 * switch to the FINAL_DELAY state and run
1784 * for one more second.
1785 */
1786 if (syncer_state == SYNCER_SHUTTING_DOWN &&
1787 net_worklist_len == 0 &&
1788 last_work_seen == syncer_delayno) {
1789 syncer_state = SYNCER_FINAL_DELAY;
1790 syncer_final_iter = SYNCER_SHUTDOWN_SPEEDUP;
1791 }
1792 } while (syncer_state != SYNCER_RUNNING && LIST_EMPTY(slp) &&
1793 LIST_EMPTY(gslp) && syncer_worklist_len > 0);
1794
1795 /*
1796 * Keep track of the last time there was anything
1797 * on the worklist other than syncer vnodes.
1798 * Return to the SHUTTING_DOWN state if any
1799 * new work appears.
1800 */
1801 if (net_worklist_len > 0 || syncer_state == SYNCER_RUNNING)
1802 last_work_seen = syncer_delayno;
1803 if (net_worklist_len > 0 && syncer_state == SYNCER_FINAL_DELAY)
1804 syncer_state = SYNCER_SHUTTING_DOWN;
1805 while (!LIST_EMPTY(slp)) {
1806 error = sync_vnode(slp, &bo, td);
1807 if (error == 1) {
1808 LIST_REMOVE(bo, bo_synclist);
1809 LIST_INSERT_HEAD(next, bo, bo_synclist);
1810 continue;
1811 }
1812 }
1813 if (!LIST_EMPTY(gslp)) {
1814 mtx_unlock(&sync_mtx);
1815 mtx_lock(&Giant);
1816 mtx_lock(&sync_mtx);
1817 while (!LIST_EMPTY(gslp)) {
1818 error = sync_vnode(gslp, &bo, td);
1819 if (error == 1) {
1820 LIST_REMOVE(bo, bo_synclist);
1821 LIST_INSERT_HEAD(gnext, bo,
1822 bo_synclist);
1823 continue;
1824 }
1825 }
1826 mtx_unlock(&Giant);
1827 }
1828 if (syncer_state == SYNCER_FINAL_DELAY && syncer_final_iter > 0)
1829 syncer_final_iter--;
1830 /*
1831 * The variable rushjob allows the kernel to speed up the
1832 * processing of the filesystem syncer process. A rushjob
1833 * value of N tells the filesystem syncer to process the next
1834 * N seconds worth of work on its queue ASAP. Currently rushjob
1835 * is used by the soft update code to speed up the filesystem
1836 * syncer process when the incore state is getting so far
1837 * ahead of the disk that the kernel memory pool is being
1838 * threatened with exhaustion.
1839 */
1840 if (rushjob > 0) {
1841 rushjob -= 1;
1842 continue;
1843 }
1844 /*
1845 * Just sleep for a short period of time between
1846 * iterations when shutting down to allow some I/O
1847 * to happen.
1848 *
1849 * If it has taken us less than a second to process the
1850 * current work, then wait. Otherwise start right over
1851 * again. We can still lose time if any single round
1852 * takes more than two seconds, but it does not really
1853 * matter as we are just trying to generally pace the
1854 * filesystem activity.
1855 */
1856 if (syncer_state != SYNCER_RUNNING)
1857 cv_timedwait(&sync_wakeup, &sync_mtx,
1858 hz / SYNCER_SHUTDOWN_SPEEDUP);
1859 else if (time_uptime == starttime)
1860 cv_timedwait(&sync_wakeup, &sync_mtx, hz);
1861 }
1862 }
1863
1864 /*
1865 * Request the syncer daemon to speed up its work.
1866 * We never push it to speed up more than half of its
1867 * normal turn time, otherwise it could take over the cpu.
1868 */
1869 int
1870 speedup_syncer(void)
1871 {
1872 int ret = 0;
1873
1874 mtx_lock(&sync_mtx);
1875 if (rushjob < syncdelay / 2) {
1876 rushjob += 1;
1877 stat_rush_requests += 1;
1878 ret = 1;
1879 }
1880 mtx_unlock(&sync_mtx);
1881 cv_broadcast(&sync_wakeup);
1882 return (ret);
1883 }
1884
1885 /*
1886 * Tell the syncer to speed up its work and run though its work
1887 * list several times, then tell it to shut down.
1888 */
1889 static void
1890 syncer_shutdown(void *arg, int howto)
1891 {
1892
1893 if (howto & RB_NOSYNC)
1894 return;
1895 mtx_lock(&sync_mtx);
1896 syncer_state = SYNCER_SHUTTING_DOWN;
1897 rushjob = 0;
1898 mtx_unlock(&sync_mtx);
1899 cv_broadcast(&sync_wakeup);
1900 kproc_shutdown(arg, howto);
1901 }
1902
1903 /*
1904 * Reassign a buffer from one vnode to another.
1905 * Used to assign file specific control information
1906 * (indirect blocks) to the vnode to which they belong.
1907 */
1908 void
1909 reassignbuf(struct buf *bp)
1910 {
1911 struct vnode *vp;
1912 struct bufobj *bo;
1913 int delay;
1914 #ifdef INVARIANTS
1915 struct bufv *bv;
1916 #endif
1917
1918 vp = bp->b_vp;
1919 bo = bp->b_bufobj;
1920 ++reassignbufcalls;
1921
1922 CTR3(KTR_BUF, "reassignbuf(%p) vp %p flags %X",
1923 bp, bp->b_vp, bp->b_flags);
1924 /*
1925 * B_PAGING flagged buffers cannot be reassigned because their vp
1926 * is not fully linked in.
1927 */
1928 if (bp->b_flags & B_PAGING)
1929 panic("cannot reassign paging buffer");
1930
1931 /*
1932 * Delete from old vnode list, if on one.
1933 */
1934 BO_LOCK(bo);
1935 if (bp->b_xflags & (BX_VNDIRTY | BX_VNCLEAN))
1936 buf_vlist_remove(bp);
1937 else
1938 panic("reassignbuf: Buffer %p not on queue.", bp);
1939 /*
1940 * If dirty, put on list of dirty buffers; otherwise insert onto list
1941 * of clean buffers.
1942 */
1943 if (bp->b_flags & B_DELWRI) {
1944 if ((bo->bo_flag & BO_ONWORKLST) == 0) {
1945 switch (vp->v_type) {
1946 case VDIR:
1947 delay = dirdelay;
1948 break;
1949 case VCHR:
1950 delay = metadelay;
1951 break;
1952 default:
1953 delay = filedelay;
1954 }
1955 vn_syncer_add_to_worklist(bo, delay);
1956 }
1957 buf_vlist_add(bp, bo, BX_VNDIRTY);
1958 } else {
1959 buf_vlist_add(bp, bo, BX_VNCLEAN);
1960
1961 if ((bo->bo_flag & BO_ONWORKLST) && bo->bo_dirty.bv_cnt == 0) {
1962 mtx_lock(&sync_mtx);
1963 LIST_REMOVE(bo, bo_synclist);
1964 syncer_worklist_len--;
1965 mtx_unlock(&sync_mtx);
1966 bo->bo_flag &= ~BO_ONWORKLST;
1967 }
1968 }
1969 #ifdef INVARIANTS
1970 bv = &bo->bo_clean;
1971 bp = TAILQ_FIRST(&bv->bv_hd);
1972 KASSERT(bp == NULL || bp->b_bufobj == bo,
1973 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo));
1974 bp = TAILQ_LAST(&bv->bv_hd, buflists);
1975 KASSERT(bp == NULL || bp->b_bufobj == bo,
1976 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo));
1977 bv = &bo->bo_dirty;
1978 bp = TAILQ_FIRST(&bv->bv_hd);
1979 KASSERT(bp == NULL || bp->b_bufobj == bo,
1980 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo));
1981 bp = TAILQ_LAST(&bv->bv_hd, buflists);
1982 KASSERT(bp == NULL || bp->b_bufobj == bo,
1983 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo));
1984 #endif
1985 BO_UNLOCK(bo);
1986 }
1987
1988 /*
1989 * Increment the use and hold counts on the vnode, taking care to reference
1990 * the driver's usecount if this is a chardev. The vholdl() will remove
1991 * the vnode from the free list if it is presently free. Requires the
1992 * vnode interlock and returns with it held.
1993 */
1994 static void
1995 v_incr_usecount(struct vnode *vp)
1996 {
1997
1998 CTR2(KTR_VFS, "%s: vp %p", __func__, vp);
1999 vp->v_usecount++;
2000 if (vp->v_type == VCHR && vp->v_rdev != NULL) {
2001 dev_lock();
2002 vp->v_rdev->si_usecount++;
2003 dev_unlock();
2004 }
2005 vholdl(vp);
2006 }
2007
2008 /*
2009 * Turn a holdcnt into a use+holdcnt such that only one call to
2010 * v_decr_usecount is needed.
2011 */
2012 static void
2013 v_upgrade_usecount(struct vnode *vp)
2014 {
2015
2016 CTR2(KTR_VFS, "%s: vp %p", __func__, vp);
2017 vp->v_usecount++;
2018 if (vp->v_type == VCHR && vp->v_rdev != NULL) {
2019 dev_lock();
2020 vp->v_rdev->si_usecount++;
2021 dev_unlock();
2022 }
2023 }
2024
2025 /*
2026 * Decrement the vnode use and hold count along with the driver's usecount
2027 * if this is a chardev. The vdropl() below releases the vnode interlock
2028 * as it may free the vnode.
2029 */
2030 static void
2031 v_decr_usecount(struct vnode *vp)
2032 {
2033
2034 ASSERT_VI_LOCKED(vp, __FUNCTION__);
2035 VNASSERT(vp->v_usecount > 0, vp,
2036 ("v_decr_usecount: negative usecount"));
2037 CTR2(KTR_VFS, "%s: vp %p", __func__, vp);
2038 vp->v_usecount--;
2039 if (vp->v_type == VCHR && vp->v_rdev != NULL) {
2040 dev_lock();
2041 vp->v_rdev->si_usecount--;
2042 dev_unlock();
2043 }
2044 vdropl(vp);
2045 }
2046
2047 /*
2048 * Decrement only the use count and driver use count. This is intended to
2049 * be paired with a follow on vdropl() to release the remaining hold count.
2050 * In this way we may vgone() a vnode with a 0 usecount without risk of
2051 * having it end up on a free list because the hold count is kept above 0.
2052 */
2053 static void
2054 v_decr_useonly(struct vnode *vp)
2055 {
2056
2057 ASSERT_VI_LOCKED(vp, __FUNCTION__);
2058 VNASSERT(vp->v_usecount > 0, vp,
2059 ("v_decr_useonly: negative usecount"));
2060 CTR2(KTR_VFS, "%s: vp %p", __func__, vp);
2061 vp->v_usecount--;
2062 if (vp->v_type == VCHR && vp->v_rdev != NULL) {
2063 dev_lock();
2064 vp->v_rdev->si_usecount--;
2065 dev_unlock();
2066 }
2067 }
2068
2069 /*
2070 * Grab a particular vnode from the free list, increment its
2071 * reference count and lock it. VI_DOOMED is set if the vnode
2072 * is being destroyed. Only callers who specify LK_RETRY will
2073 * see doomed vnodes. If inactive processing was delayed in
2074 * vput try to do it here.
2075 */
2076 int
2077 vget(struct vnode *vp, int flags, struct thread *td)
2078 {
2079 int error;
2080
2081 error = 0;
2082 VFS_ASSERT_GIANT(vp->v_mount);
2083 VNASSERT((flags & LK_TYPE_MASK) != 0, vp,
2084 ("vget: invalid lock operation"));
2085 CTR3(KTR_VFS, "%s: vp %p with flags %d", __func__, vp, flags);
2086
2087 if ((flags & LK_INTERLOCK) == 0)
2088 VI_LOCK(vp);
2089 vholdl(vp);
2090 if ((error = vn_lock(vp, flags | LK_INTERLOCK)) != 0) {
2091 vdrop(vp);
2092 CTR2(KTR_VFS, "%s: impossible to lock vnode %p", __func__,
2093 vp);
2094 return (error);
2095 }
2096 if (vp->v_iflag & VI_DOOMED && (flags & LK_RETRY) == 0)
2097 panic("vget: vn_lock failed to return ENOENT\n");
2098 VI_LOCK(vp);
2099 /* Upgrade our holdcnt to a usecount. */
2100 v_upgrade_usecount(vp);
2101 /*
2102 * We don't guarantee that any particular close will
2103 * trigger inactive processing so just make a best effort
2104 * here at preventing a reference to a removed file. If
2105 * we don't succeed no harm is done.
2106 */
2107 if (vp->v_iflag & VI_OWEINACT) {
2108 if (VOP_ISLOCKED(vp) == LK_EXCLUSIVE &&
2109 (flags & LK_NOWAIT) == 0)
2110 vinactive(vp, td);
2111 vp->v_iflag &= ~VI_OWEINACT;
2112 }
2113 VI_UNLOCK(vp);
2114 return (0);
2115 }
2116
2117 /*
2118 * Increase the reference count of a vnode.
2119 */
2120 void
2121 vref(struct vnode *vp)
2122 {
2123
2124 CTR2(KTR_VFS, "%s: vp %p", __func__, vp);
2125 VI_LOCK(vp);
2126 v_incr_usecount(vp);
2127 VI_UNLOCK(vp);
2128 }
2129
2130 /*
2131 * Return reference count of a vnode.
2132 *
2133 * The results of this call are only guaranteed when some mechanism other
2134 * than the VI lock is used to stop other processes from gaining references
2135 * to the vnode. This may be the case if the caller holds the only reference.
2136 * This is also useful when stale data is acceptable as race conditions may
2137 * be accounted for by some other means.
2138 */
2139 int
2140 vrefcnt(struct vnode *vp)
2141 {
2142 int usecnt;
2143
2144 VI_LOCK(vp);
2145 usecnt = vp->v_usecount;
2146 VI_UNLOCK(vp);
2147
2148 return (usecnt);
2149 }
2150
2151 #define VPUTX_VRELE 1
2152 #define VPUTX_VPUT 2
2153 #define VPUTX_VUNREF 3
2154
2155 static void
2156 vputx(struct vnode *vp, int func)
2157 {
2158 int error;
2159
2160 KASSERT(vp != NULL, ("vputx: null vp"));
2161 if (func == VPUTX_VUNREF)
2162 ASSERT_VOP_ELOCKED(vp, "vunref");
2163 else if (func == VPUTX_VPUT)
2164 ASSERT_VOP_LOCKED(vp, "vput");
2165 else
2166 KASSERT(func == VPUTX_VRELE, ("vputx: wrong func"));
2167 VFS_ASSERT_GIANT(vp->v_mount);
2168 CTR2(KTR_VFS, "%s: vp %p", __func__, vp);
2169 VI_LOCK(vp);
2170
2171 /* Skip this v_writecount check if we're going to panic below. */
2172 VNASSERT(vp->v_writecount < vp->v_usecount || vp->v_usecount < 1, vp,
2173 ("vputx: missed vn_close"));
2174 error = 0;
2175
2176 if (vp->v_usecount > 1 || ((vp->v_iflag & VI_DOINGINACT) &&
2177 vp->v_usecount == 1)) {
2178 if (func == VPUTX_VPUT)
2179 VOP_UNLOCK(vp, 0);
2180 v_decr_usecount(vp);
2181 return;
2182 }
2183
2184 if (vp->v_usecount != 1) {
2185 #ifdef DIAGNOSTIC
2186 vprint("vputx: negative ref count", vp);
2187 #endif
2188 panic("vputx: negative ref cnt");
2189 }
2190 CTR2(KTR_VFS, "%s: return vnode %p to the freelist", __func__, vp);
2191 /*
2192 * We want to hold the vnode until the inactive finishes to
2193 * prevent vgone() races. We drop the use count here and the
2194 * hold count below when we're done.
2195 */
2196 v_decr_useonly(vp);
2197 /*
2198 * We must call VOP_INACTIVE with the node locked. Mark
2199 * as VI_DOINGINACT to avoid recursion.
2200 */
2201 vp->v_iflag |= VI_OWEINACT;
2202 if (func == VPUTX_VRELE) {
2203 error = vn_lock(vp, LK_EXCLUSIVE | LK_INTERLOCK);
2204 VI_LOCK(vp);
2205 } else if (func == VPUTX_VPUT && VOP_ISLOCKED(vp) != LK_EXCLUSIVE) {
2206 error = VOP_LOCK(vp, LK_UPGRADE | LK_INTERLOCK | LK_NOWAIT);
2207 VI_LOCK(vp);
2208 }
2209 if (vp->v_usecount > 0)
2210 vp->v_iflag &= ~VI_OWEINACT;
2211 if (error == 0) {
2212 if (vp->v_iflag & VI_OWEINACT)
2213 vinactive(vp, curthread);
2214 if (func != VPUTX_VUNREF)
2215 VOP_UNLOCK(vp, 0);
2216 }
2217 vdropl(vp);
2218 }
2219
2220 /*
2221 * Vnode put/release.
2222 * If count drops to zero, call inactive routine and return to freelist.
2223 */
2224 void
2225 vrele(struct vnode *vp)
2226 {
2227
2228 vputx(vp, VPUTX_VRELE);
2229 }
2230
2231 /*
2232 * Release an already locked vnode. This give the same effects as
2233 * unlock+vrele(), but takes less time and avoids releasing and
2234 * re-aquiring the lock (as vrele() acquires the lock internally.)
2235 */
2236 void
2237 vput(struct vnode *vp)
2238 {
2239
2240 vputx(vp, VPUTX_VPUT);
2241 }
2242
2243 /*
2244 * Release an exclusively locked vnode. Do not unlock the vnode lock.
2245 */
2246 void
2247 vunref(struct vnode *vp)
2248 {
2249
2250 vputx(vp, VPUTX_VUNREF);
2251 }
2252
2253 /*
2254 * Somebody doesn't want the vnode recycled.
2255 */
2256 void
2257 vhold(struct vnode *vp)
2258 {
2259
2260 VI_LOCK(vp);
2261 vholdl(vp);
2262 VI_UNLOCK(vp);
2263 }
2264
2265 void
2266 vholdl(struct vnode *vp)
2267 {
2268
2269 CTR2(KTR_VFS, "%s: vp %p", __func__, vp);
2270 vp->v_holdcnt++;
2271 if (VSHOULDBUSY(vp))
2272 vbusy(vp);
2273 }
2274
2275 /*
2276 * Note that there is one less who cares about this vnode. vdrop() is the
2277 * opposite of vhold().
2278 */
2279 void
2280 vdrop(struct vnode *vp)
2281 {
2282
2283 VI_LOCK(vp);
2284 vdropl(vp);
2285 }
2286
2287 /*
2288 * Drop the hold count of the vnode. If this is the last reference to
2289 * the vnode we will free it if it has been vgone'd otherwise it is
2290 * placed on the free list.
2291 */
2292 void
2293 vdropl(struct vnode *vp)
2294 {
2295
2296 ASSERT_VI_LOCKED(vp, "vdropl");
2297 CTR2(KTR_VFS, "%s: vp %p", __func__, vp);
2298 if (vp->v_holdcnt <= 0)
2299 panic("vdrop: holdcnt %d", vp->v_holdcnt);
2300 vp->v_holdcnt--;
2301 if (vp->v_holdcnt == 0) {
2302 if (vp->v_iflag & VI_DOOMED) {
2303 CTR2(KTR_VFS, "%s: destroying the vnode %p", __func__,
2304 vp);
2305 vdestroy(vp);
2306 return;
2307 } else
2308 vfree(vp);
2309 }
2310 VI_UNLOCK(vp);
2311 }
2312
2313 /*
2314 * Call VOP_INACTIVE on the vnode and manage the DOINGINACT and OWEINACT
2315 * flags. DOINGINACT prevents us from recursing in calls to vinactive.
2316 * OWEINACT tracks whether a vnode missed a call to inactive due to a
2317 * failed lock upgrade.
2318 */
2319 static void
2320 vinactive(struct vnode *vp, struct thread *td)
2321 {
2322
2323 ASSERT_VOP_ELOCKED(vp, "vinactive");
2324 ASSERT_VI_LOCKED(vp, "vinactive");
2325 VNASSERT((vp->v_iflag & VI_DOINGINACT) == 0, vp,
2326 ("vinactive: recursed on VI_DOINGINACT"));
2327 CTR2(KTR_VFS, "%s: vp %p", __func__, vp);
2328 vp->v_iflag |= VI_DOINGINACT;
2329 vp->v_iflag &= ~VI_OWEINACT;
2330 VI_UNLOCK(vp);
2331 VOP_INACTIVE(vp, td);
2332 VI_LOCK(vp);
2333 VNASSERT(vp->v_iflag & VI_DOINGINACT, vp,
2334 ("vinactive: lost VI_DOINGINACT"));
2335 vp->v_iflag &= ~VI_DOINGINACT;
2336 }
2337
2338 /*
2339 * Remove any vnodes in the vnode table belonging to mount point mp.
2340 *
2341 * If FORCECLOSE is not specified, there should not be any active ones,
2342 * return error if any are found (nb: this is a user error, not a
2343 * system error). If FORCECLOSE is specified, detach any active vnodes
2344 * that are found.
2345 *
2346 * If WRITECLOSE is set, only flush out regular file vnodes open for
2347 * writing.
2348 *
2349 * SKIPSYSTEM causes any vnodes marked VV_SYSTEM to be skipped.
2350 *
2351 * `rootrefs' specifies the base reference count for the root vnode
2352 * of this filesystem. The root vnode is considered busy if its
2353 * v_usecount exceeds this value. On a successful return, vflush(, td)
2354 * will call vrele() on the root vnode exactly rootrefs times.
2355 * If the SKIPSYSTEM or WRITECLOSE flags are specified, rootrefs must
2356 * be zero.
2357 */
2358 #ifdef DIAGNOSTIC
2359 static int busyprt = 0; /* print out busy vnodes */
2360 SYSCTL_INT(_debug, OID_AUTO, busyprt, CTLFLAG_RW, &busyprt, 0, "");
2361 #endif
2362
2363 int
2364 vflush( struct mount *mp, int rootrefs, int flags, struct thread *td)
2365 {
2366 struct vnode *vp, *mvp, *rootvp = NULL;
2367 struct vattr vattr;
2368 int busy = 0, error;
2369
2370 CTR4(KTR_VFS, "%s: mp %p with rootrefs %d and flags %d", __func__, mp,
2371 rootrefs, flags);
2372 if (rootrefs > 0) {
2373 KASSERT((flags & (SKIPSYSTEM | WRITECLOSE)) == 0,
2374 ("vflush: bad args"));
2375 /*
2376 * Get the filesystem root vnode. We can vput() it
2377 * immediately, since with rootrefs > 0, it won't go away.
2378 */
2379 if ((error = VFS_ROOT(mp, LK_EXCLUSIVE, &rootvp)) != 0) {
2380 CTR2(KTR_VFS, "%s: vfs_root lookup failed with %d",
2381 __func__, error);
2382 return (error);
2383 }
2384 vput(rootvp);
2385
2386 }
2387 MNT_ILOCK(mp);
2388 loop:
2389 MNT_VNODE_FOREACH(vp, mp, mvp) {
2390
2391 VI_LOCK(vp);
2392 vholdl(vp);
2393 MNT_IUNLOCK(mp);
2394 error = vn_lock(vp, LK_INTERLOCK | LK_EXCLUSIVE);
2395 if (error) {
2396 vdrop(vp);
2397 MNT_ILOCK(mp);
2398 MNT_VNODE_FOREACH_ABORT_ILOCKED(mp, mvp);
2399 goto loop;
2400 }
2401 /*
2402 * Skip over a vnodes marked VV_SYSTEM.
2403 */
2404 if ((flags & SKIPSYSTEM) && (vp->v_vflag & VV_SYSTEM)) {
2405 VOP_UNLOCK(vp, 0);
2406 vdrop(vp);
2407 MNT_ILOCK(mp);
2408 continue;
2409 }
2410 /*
2411 * If WRITECLOSE is set, flush out unlinked but still open
2412 * files (even if open only for reading) and regular file
2413 * vnodes open for writing.
2414 */
2415 if (flags & WRITECLOSE) {
2416 error = VOP_GETATTR(vp, &vattr, td->td_ucred);
2417 VI_LOCK(vp);
2418
2419 if ((vp->v_type == VNON ||
2420 (error == 0 && vattr.va_nlink > 0)) &&
2421 (vp->v_writecount == 0 || vp->v_type != VREG)) {
2422 VOP_UNLOCK(vp, 0);
2423 vdropl(vp);
2424 MNT_ILOCK(mp);
2425 continue;
2426 }
2427 } else
2428 VI_LOCK(vp);
2429 /*
2430 * With v_usecount == 0, all we need to do is clear out the
2431 * vnode data structures and we are done.
2432 *
2433 * If FORCECLOSE is set, forcibly close the vnode.
2434 */
2435 if (vp->v_usecount == 0 || (flags & FORCECLOSE)) {
2436 VNASSERT(vp->v_usecount == 0 ||
2437 (vp->v_type != VCHR && vp->v_type != VBLK), vp,
2438 ("device VNODE %p is FORCECLOSED", vp));
2439 vgonel(vp);
2440 } else {
2441 busy++;
2442 #ifdef DIAGNOSTIC
2443 if (busyprt)
2444 vprint("vflush: busy vnode", vp);
2445 #endif
2446 }
2447 VOP_UNLOCK(vp, 0);
2448 vdropl(vp);
2449 MNT_ILOCK(mp);
2450 }
2451 MNT_IUNLOCK(mp);
2452 if (rootrefs > 0 && (flags & FORCECLOSE) == 0) {
2453 /*
2454 * If just the root vnode is busy, and if its refcount
2455 * is equal to `rootrefs', then go ahead and kill it.
2456 */
2457 VI_LOCK(rootvp);
2458 KASSERT(busy > 0, ("vflush: not busy"));
2459 VNASSERT(rootvp->v_usecount >= rootrefs, rootvp,
2460 ("vflush: usecount %d < rootrefs %d",
2461 rootvp->v_usecount, rootrefs));
2462 if (busy == 1 && rootvp->v_usecount == rootrefs) {
2463 VOP_LOCK(rootvp, LK_EXCLUSIVE|LK_INTERLOCK);
2464 vgone(rootvp);
2465 VOP_UNLOCK(rootvp, 0);
2466 busy = 0;
2467 } else
2468 VI_UNLOCK(rootvp);
2469 }
2470 if (busy) {
2471 CTR2(KTR_VFS, "%s: failing as %d vnodes are busy", __func__,
2472 busy);
2473 return (EBUSY);
2474 }
2475 for (; rootrefs > 0; rootrefs--)
2476 vrele(rootvp);
2477 return (0);
2478 }
2479
2480 /*
2481 * Recycle an unused vnode to the front of the free list.
2482 */
2483 int
2484 vrecycle(struct vnode *vp, struct thread *td)
2485 {
2486 int recycled;
2487
2488 ASSERT_VOP_ELOCKED(vp, "vrecycle");
2489 CTR2(KTR_VFS, "%s: vp %p", __func__, vp);
2490 recycled = 0;
2491 VI_LOCK(vp);
2492 if (vp->v_usecount == 0) {
2493 recycled = 1;
2494 vgonel(vp);
2495 }
2496 VI_UNLOCK(vp);
2497 return (recycled);
2498 }
2499
2500 /*
2501 * Eliminate all activity associated with a vnode
2502 * in preparation for reuse.
2503 */
2504 void
2505 vgone(struct vnode *vp)
2506 {
2507 VI_LOCK(vp);
2508 vgonel(vp);
2509 VI_UNLOCK(vp);
2510 }
2511
2512 /*
2513 * vgone, with the vp interlock held.
2514 */
2515 void
2516 vgonel(struct vnode *vp)
2517 {
2518 struct thread *td;
2519 int oweinact;
2520 int active;
2521 struct mount *mp;
2522
2523 ASSERT_VOP_ELOCKED(vp, "vgonel");
2524 ASSERT_VI_LOCKED(vp, "vgonel");
2525 VNASSERT(vp->v_holdcnt, vp,
2526 ("vgonel: vp %p has no reference.", vp));
2527 CTR2(KTR_VFS, "%s: vp %p", __func__, vp);
2528 td = curthread;
2529
2530 /*
2531 * Don't vgonel if we're already doomed.
2532 */
2533 if (vp->v_iflag & VI_DOOMED)
2534 return;
2535 vp->v_iflag |= VI_DOOMED;
2536 /*
2537 * Check to see if the vnode is in use. If so, we have to call
2538 * VOP_CLOSE() and VOP_INACTIVE().
2539 */
2540 active = vp->v_usecount;
2541 oweinact = (vp->v_iflag & VI_OWEINACT);
2542 VI_UNLOCK(vp);
2543 /*
2544 * Clean out any buffers associated with the vnode.
2545 * If the flush fails, just toss the buffers.
2546 */
2547 mp = NULL;
2548 if (!TAILQ_EMPTY(&vp->v_bufobj.bo_dirty.bv_hd))
2549 (void) vn_start_secondary_write(vp, &mp, V_WAIT);
2550 if (vinvalbuf(vp, V_SAVE, 0, 0) != 0)
2551 vinvalbuf(vp, 0, 0, 0);
2552
2553 /*
2554 * If purging an active vnode, it must be closed and
2555 * deactivated before being reclaimed.
2556 */
2557 if (active)
2558 VOP_CLOSE(vp, FNONBLOCK, NOCRED, td);
2559 if (oweinact || active) {
2560 VI_LOCK(vp);
2561 if ((vp->v_iflag & VI_DOINGINACT) == 0)
2562 vinactive(vp, td);
2563 VI_UNLOCK(vp);
2564 }
2565 /*
2566 * Reclaim the vnode.
2567 */
2568 if (VOP_RECLAIM(vp, td))
2569 panic("vgone: cannot reclaim");
2570 if (mp != NULL)
2571 vn_finished_secondary_write(mp);
2572 VNASSERT(vp->v_object == NULL, vp,
2573 ("vop_reclaim left v_object vp=%p, tag=%s", vp, vp->v_tag));
2574 /*
2575 * Clear the advisory locks and wake up waiting threads.
2576 */
2577 lf_purgelocks(vp, &(vp->v_lockf));
2578 /*
2579 * Delete from old mount point vnode list.
2580 */
2581 delmntque(vp);
2582 cache_purge(vp);
2583 /*
2584 * Done with purge, reset to the standard lock and invalidate
2585 * the vnode.
2586 */
2587 VI_LOCK(vp);
2588 vp->v_vnlock = &vp->v_lock;
2589 vp->v_op = &dead_vnodeops;
2590 vp->v_tag = "none";
2591 vp->v_type = VBAD;
2592 }
2593
2594 /*
2595 * Calculate the total number of references to a special device.
2596 */
2597 int
2598 vcount(struct vnode *vp)
2599 {
2600 int count;
2601
2602 dev_lock();
2603 count = vp->v_rdev->si_usecount;
2604 dev_unlock();
2605 return (count);
2606 }
2607
2608 /*
2609 * Same as above, but using the struct cdev *as argument
2610 */
2611 int
2612 count_dev(struct cdev *dev)
2613 {
2614 int count;
2615
2616 dev_lock();
2617 count = dev->si_usecount;
2618 dev_unlock();
2619 return(count);
2620 }
2621
2622 /*
2623 * Print out a description of a vnode.
2624 */
2625 static char *typename[] =
2626 {"VNON", "VREG", "VDIR", "VBLK", "VCHR", "VLNK", "VSOCK", "VFIFO", "VBAD",
2627 "VMARKER"};
2628
2629 void
2630 vn_printf(struct vnode *vp, const char *fmt, ...)
2631 {
2632 va_list ap;
2633 char buf[256], buf2[16];
2634 u_long flags;
2635
2636 va_start(ap, fmt);
2637 vprintf(fmt, ap);
2638 va_end(ap);
2639 printf("%p: ", (void *)vp);
2640 printf("tag %s, type %s\n", vp->v_tag, typename[vp->v_type]);
2641 printf(" usecount %d, writecount %d, refcount %d mountedhere %p\n",
2642 vp->v_usecount, vp->v_writecount, vp->v_holdcnt, vp->v_mountedhere);
2643 buf[0] = '\0';
2644 buf[1] = '\0';
2645 if (vp->v_vflag & VV_ROOT)
2646 strlcat(buf, "|VV_ROOT", sizeof(buf));
2647 if (vp->v_vflag & VV_ISTTY)
2648 strlcat(buf, "|VV_ISTTY", sizeof(buf));
2649 if (vp->v_vflag & VV_NOSYNC)
2650 strlcat(buf, "|VV_NOSYNC", sizeof(buf));
2651 if (vp->v_vflag & VV_CACHEDLABEL)
2652 strlcat(buf, "|VV_CACHEDLABEL", sizeof(buf));
2653 if (vp->v_vflag & VV_TEXT)
2654 strlcat(buf, "|VV_TEXT", sizeof(buf));
2655 if (vp->v_vflag & VV_COPYONWRITE)
2656 strlcat(buf, "|VV_COPYONWRITE", sizeof(buf));
2657 if (vp->v_vflag & VV_SYSTEM)
2658 strlcat(buf, "|VV_SYSTEM", sizeof(buf));
2659 if (vp->v_vflag & VV_PROCDEP)
2660 strlcat(buf, "|VV_PROCDEP", sizeof(buf));
2661 if (vp->v_vflag & VV_NOKNOTE)
2662 strlcat(buf, "|VV_NOKNOTE", sizeof(buf));
2663 if (vp->v_vflag & VV_DELETED)
2664 strlcat(buf, "|VV_DELETED", sizeof(buf));
2665 if (vp->v_vflag & VV_MD)
2666 strlcat(buf, "|VV_MD", sizeof(buf));
2667 flags = vp->v_vflag & ~(VV_ROOT | VV_ISTTY | VV_NOSYNC |
2668 VV_CACHEDLABEL | VV_TEXT | VV_COPYONWRITE | VV_SYSTEM | VV_PROCDEP |
2669 VV_NOKNOTE | VV_DELETED | VV_MD);
2670 if (flags != 0) {
2671 snprintf(buf2, sizeof(buf2), "|VV(0x%lx)", flags);
2672 strlcat(buf, buf2, sizeof(buf));
2673 }
2674 if (vp->v_iflag & VI_MOUNT)
2675 strlcat(buf, "|VI_MOUNT", sizeof(buf));
2676 if (vp->v_iflag & VI_AGE)
2677 strlcat(buf, "|VI_AGE", sizeof(buf));
2678 if (vp->v_iflag & VI_DOOMED)
2679 strlcat(buf, "|VI_DOOMED", sizeof(buf));
2680 if (vp->v_iflag & VI_FREE)
2681 strlcat(buf, "|VI_FREE", sizeof(buf));
2682 if (vp->v_iflag & VI_DOINGINACT)
2683 strlcat(buf, "|VI_DOINGINACT", sizeof(buf));
2684 if (vp->v_iflag & VI_OWEINACT)
2685 strlcat(buf, "|VI_OWEINACT", sizeof(buf));
2686 flags = vp->v_iflag & ~(VI_MOUNT | VI_AGE | VI_DOOMED | VI_FREE |
2687 VI_DOINGINACT | VI_OWEINACT);
2688 if (flags != 0) {
2689 snprintf(buf2, sizeof(buf2), "|VI(0x%lx)", flags);
2690 strlcat(buf, buf2, sizeof(buf));
2691 }
2692 printf(" flags (%s)\n", buf + 1);
2693 if (mtx_owned(VI_MTX(vp)))
2694 printf(" VI_LOCKed");
2695 if (vp->v_object != NULL)
2696 printf(" v_object %p ref %d pages %d\n",
2697 vp->v_object, vp->v_object->ref_count,
2698 vp->v_object->resident_page_count);
2699 printf(" ");
2700 lockmgr_printinfo(vp->v_vnlock);
2701 if (vp->v_data != NULL)
2702 VOP_PRINT(vp);
2703 }
2704
2705 #ifdef DDB
2706 /*
2707 * List all of the locked vnodes in the system.
2708 * Called when debugging the kernel.
2709 */
2710 DB_SHOW_COMMAND(lockedvnods, lockedvnodes)
2711 {
2712 struct mount *mp, *nmp;
2713 struct vnode *vp;
2714
2715 /*
2716 * Note: because this is DDB, we can't obey the locking semantics
2717 * for these structures, which means we could catch an inconsistent
2718 * state and dereference a nasty pointer. Not much to be done
2719 * about that.
2720 */
2721 db_printf("Locked vnodes\n");
2722 for (mp = TAILQ_FIRST(&mountlist); mp != NULL; mp = nmp) {
2723 nmp = TAILQ_NEXT(mp, mnt_list);
2724 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) {
2725 if (vp->v_type != VMARKER &&
2726 VOP_ISLOCKED(vp))
2727 vprint("", vp);
2728 }
2729 nmp = TAILQ_NEXT(mp, mnt_list);
2730 }
2731 }
2732
2733 /*
2734 * Show details about the given vnode.
2735 */
2736 DB_SHOW_COMMAND(vnode, db_show_vnode)
2737 {
2738 struct vnode *vp;
2739
2740 if (!have_addr)
2741 return;
2742 vp = (struct vnode *)addr;
2743 vn_printf(vp, "vnode ");
2744 }
2745
2746 /*
2747 * Show details about the given mount point.
2748 */
2749 DB_SHOW_COMMAND(mount, db_show_mount)
2750 {
2751 struct mount *mp;
2752 struct vfsopt *opt;
2753 struct statfs *sp;
2754 struct vnode *vp;
2755 char buf[512];
2756 u_int flags;
2757
2758 if (!have_addr) {
2759 /* No address given, print short info about all mount points. */
2760 TAILQ_FOREACH(mp, &mountlist, mnt_list) {
2761 db_printf("%p %s on %s (%s)\n", mp,
2762 mp->mnt_stat.f_mntfromname,
2763 mp->mnt_stat.f_mntonname,
2764 mp->mnt_stat.f_fstypename);
2765 if (db_pager_quit)
2766 break;
2767 }
2768 db_printf("\nMore info: show mount <addr>\n");
2769 return;
2770 }
2771
2772 mp = (struct mount *)addr;
2773 db_printf("%p %s on %s (%s)\n", mp, mp->mnt_stat.f_mntfromname,
2774 mp->mnt_stat.f_mntonname, mp->mnt_stat.f_fstypename);
2775
2776 buf[0] = '\0';
2777 flags = mp->mnt_flag;
2778 #define MNT_FLAG(flag) do { \
2779 if (flags & (flag)) { \
2780 if (buf[0] != '\0') \
2781 strlcat(buf, ", ", sizeof(buf)); \
2782 strlcat(buf, (#flag) + 4, sizeof(buf)); \
2783 flags &= ~(flag); \
2784 } \
2785 } while (0)
2786 MNT_FLAG(MNT_RDONLY);
2787 MNT_FLAG(MNT_SYNCHRONOUS);
2788 MNT_FLAG(MNT_NOEXEC);
2789 MNT_FLAG(MNT_NOSUID);
2790 MNT_FLAG(MNT_UNION);
2791 MNT_FLAG(MNT_ASYNC);
2792 MNT_FLAG(MNT_SUIDDIR);
2793 MNT_FLAG(MNT_SOFTDEP);
2794 MNT_FLAG(MNT_NOSYMFOLLOW);
2795 MNT_FLAG(MNT_GJOURNAL);
2796 MNT_FLAG(MNT_MULTILABEL);
2797 MNT_FLAG(MNT_ACLS);
2798 MNT_FLAG(MNT_NOATIME);
2799 MNT_FLAG(MNT_NOCLUSTERR);
2800 MNT_FLAG(MNT_NOCLUSTERW);
2801 MNT_FLAG(MNT_NFS4ACLS);
2802 MNT_FLAG(MNT_EXRDONLY);
2803 MNT_FLAG(MNT_EXPORTED);
2804 MNT_FLAG(MNT_DEFEXPORTED);
2805 MNT_FLAG(MNT_EXPORTANON);
2806 MNT_FLAG(MNT_EXKERB);
2807 MNT_FLAG(MNT_EXPUBLIC);
2808 MNT_FLAG(MNT_LOCAL);
2809 MNT_FLAG(MNT_QUOTA);
2810 MNT_FLAG(MNT_ROOTFS);
2811 MNT_FLAG(MNT_USER);
2812 MNT_FLAG(MNT_IGNORE);
2813 MNT_FLAG(MNT_UPDATE);
2814 MNT_FLAG(MNT_DELEXPORT);
2815 MNT_FLAG(MNT_RELOAD);
2816 MNT_FLAG(MNT_FORCE);
2817 MNT_FLAG(MNT_SNAPSHOT);
2818 MNT_FLAG(MNT_BYFSID);
2819 #undef MNT_FLAG
2820 if (flags != 0) {
2821 if (buf[0] != '\0')
2822 strlcat(buf, ", ", sizeof(buf));
2823 snprintf(buf + strlen(buf), sizeof(buf) - strlen(buf),
2824 "0x%08x", flags);
2825 }
2826 db_printf(" mnt_flag = %s\n", buf);
2827
2828 buf[0] = '\0';
2829 flags = mp->mnt_kern_flag;
2830 #define MNT_KERN_FLAG(flag) do { \
2831 if (flags & (flag)) { \
2832 if (buf[0] != '\0') \
2833 strlcat(buf, ", ", sizeof(buf)); \
2834 strlcat(buf, (#flag) + 5, sizeof(buf)); \
2835 flags &= ~(flag); \
2836 } \
2837 } while (0)
2838 MNT_KERN_FLAG(MNTK_UNMOUNTF);
2839 MNT_KERN_FLAG(MNTK_ASYNC);
2840 MNT_KERN_FLAG(MNTK_SOFTDEP);
2841 MNT_KERN_FLAG(MNTK_NOINSMNTQ);
2842 MNT_KERN_FLAG(MNTK_UNMOUNT);
2843 MNT_KERN_FLAG(MNTK_MWAIT);
2844 MNT_KERN_FLAG(MNTK_SUSPEND);
2845 MNT_KERN_FLAG(MNTK_SUSPEND2);
2846 MNT_KERN_FLAG(MNTK_SUSPENDED);
2847 MNT_KERN_FLAG(MNTK_MPSAFE);
2848 MNT_KERN_FLAG(MNTK_NOKNOTE);
2849 MNT_KERN_FLAG(MNTK_LOOKUP_SHARED);
2850 #undef MNT_KERN_FLAG
2851 if (flags != 0) {
2852 if (buf[0] != '\0')
2853 strlcat(buf, ", ", sizeof(buf));
2854 snprintf(buf + strlen(buf), sizeof(buf) - strlen(buf),
2855 "0x%08x", flags);
2856 }
2857 db_printf(" mnt_kern_flag = %s\n", buf);
2858
2859 db_printf(" mnt_opt = ");
2860 opt = TAILQ_FIRST(mp->mnt_opt);
2861 if (opt != NULL) {
2862 db_printf("%s", opt->name);
2863 opt = TAILQ_NEXT(opt, link);
2864 while (opt != NULL) {
2865 db_printf(", %s", opt->name);
2866 opt = TAILQ_NEXT(opt, link);
2867 }
2868 }
2869 db_printf("\n");
2870
2871 sp = &mp->mnt_stat;
2872 db_printf(" mnt_stat = { version=%u type=%u flags=0x%016jx "
2873 "bsize=%ju iosize=%ju blocks=%ju bfree=%ju bavail=%jd files=%ju "
2874 "ffree=%jd syncwrites=%ju asyncwrites=%ju syncreads=%ju "
2875 "asyncreads=%ju namemax=%u owner=%u fsid=[%d, %d] }\n",
2876 (u_int)sp->f_version, (u_int)sp->f_type, (uintmax_t)sp->f_flags,
2877 (uintmax_t)sp->f_bsize, (uintmax_t)sp->f_iosize,
2878 (uintmax_t)sp->f_blocks, (uintmax_t)sp->f_bfree,
2879 (intmax_t)sp->f_bavail, (uintmax_t)sp->f_files,
2880 (intmax_t)sp->f_ffree, (uintmax_t)sp->f_syncwrites,
2881 (uintmax_t)sp->f_asyncwrites, (uintmax_t)sp->f_syncreads,
2882 (uintmax_t)sp->f_asyncreads, (u_int)sp->f_namemax,
2883 (u_int)sp->f_owner, (int)sp->f_fsid.val[0], (int)sp->f_fsid.val[1]);
2884
2885 db_printf(" mnt_cred = { uid=%u ruid=%u",
2886 (u_int)mp->mnt_cred->cr_uid, (u_int)mp->mnt_cred->cr_ruid);
2887 if (jailed(mp->mnt_cred))
2888 db_printf(", jail=%d", mp->mnt_cred->cr_prison->pr_id);
2889 db_printf(" }\n");
2890 db_printf(" mnt_ref = %d\n", mp->mnt_ref);
2891 db_printf(" mnt_gen = %d\n", mp->mnt_gen);
2892 db_printf(" mnt_nvnodelistsize = %d\n", mp->mnt_nvnodelistsize);
2893 db_printf(" mnt_writeopcount = %d\n", mp->mnt_writeopcount);
2894 db_printf(" mnt_noasync = %u\n", mp->mnt_noasync);
2895 db_printf(" mnt_maxsymlinklen = %d\n", mp->mnt_maxsymlinklen);
2896 db_printf(" mnt_iosize_max = %d\n", mp->mnt_iosize_max);
2897 db_printf(" mnt_hashseed = %u\n", mp->mnt_hashseed);
2898 db_printf(" mnt_secondary_writes = %d\n", mp->mnt_secondary_writes);
2899 db_printf(" mnt_secondary_accwrites = %d\n",
2900 mp->mnt_secondary_accwrites);
2901 db_printf(" mnt_gjprovider = %s\n",
2902 mp->mnt_gjprovider != NULL ? mp->mnt_gjprovider : "NULL");
2903 db_printf("\n");
2904
2905 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) {
2906 if (vp->v_type != VMARKER) {
2907 vn_printf(vp, "vnode ");
2908 if (db_pager_quit)
2909 break;
2910 }
2911 }
2912 }
2913 #endif /* DDB */
2914
2915 /*
2916 * Fill in a struct xvfsconf based on a struct vfsconf.
2917 */
2918 static void
2919 vfsconf2x(struct vfsconf *vfsp, struct xvfsconf *xvfsp)
2920 {
2921
2922 strcpy(xvfsp->vfc_name, vfsp->vfc_name);
2923 xvfsp->vfc_typenum = vfsp->vfc_typenum;
2924 xvfsp->vfc_refcount = vfsp->vfc_refcount;
2925 xvfsp->vfc_flags = vfsp->vfc_flags;
2926 /*
2927 * These are unused in userland, we keep them
2928 * to not break binary compatibility.
2929 */
2930 xvfsp->vfc_vfsops = NULL;
2931 xvfsp->vfc_next = NULL;
2932 }
2933
2934 /*
2935 * Top level filesystem related information gathering.
2936 */
2937 static int
2938 sysctl_vfs_conflist(SYSCTL_HANDLER_ARGS)
2939 {
2940 struct vfsconf *vfsp;
2941 struct xvfsconf xvfsp;
2942 int error;
2943
2944 error = 0;
2945 TAILQ_FOREACH(vfsp, &vfsconf, vfc_list) {
2946 bzero(&xvfsp, sizeof(xvfsp));
2947 vfsconf2x(vfsp, &xvfsp);
2948 error = SYSCTL_OUT(req, &xvfsp, sizeof xvfsp);
2949 if (error)
2950 break;
2951 }
2952 return (error);
2953 }
2954
2955 SYSCTL_PROC(_vfs, OID_AUTO, conflist, CTLFLAG_RD, NULL, 0, sysctl_vfs_conflist,
2956 "S,xvfsconf", "List of all configured filesystems");
2957
2958 #ifndef BURN_BRIDGES
2959 static int sysctl_ovfs_conf(SYSCTL_HANDLER_ARGS);
2960
2961 static int
2962 vfs_sysctl(SYSCTL_HANDLER_ARGS)
2963 {
2964 int *name = (int *)arg1 - 1; /* XXX */
2965 u_int namelen = arg2 + 1; /* XXX */
2966 struct vfsconf *vfsp;
2967 struct xvfsconf xvfsp;
2968
2969 printf("WARNING: userland calling deprecated sysctl, "
2970 "please rebuild world\n");
2971
2972 #if 1 || defined(COMPAT_PRELITE2)
2973 /* Resolve ambiguity between VFS_VFSCONF and VFS_GENERIC. */
2974 if (namelen == 1)
2975 return (sysctl_ovfs_conf(oidp, arg1, arg2, req));
2976 #endif
2977
2978 switch (name[1]) {
2979 case VFS_MAXTYPENUM:
2980 if (namelen != 2)
2981 return (ENOTDIR);
2982 return (SYSCTL_OUT(req, &maxvfsconf, sizeof(int)));
2983 case VFS_CONF:
2984 if (namelen != 3)
2985 return (ENOTDIR); /* overloaded */
2986 TAILQ_FOREACH(vfsp, &vfsconf, vfc_list)
2987 if (vfsp->vfc_typenum == name[2])
2988 break;
2989 if (vfsp == NULL)
2990 return (EOPNOTSUPP);
2991 bzero(&xvfsp, sizeof(xvfsp));
2992 vfsconf2x(vfsp, &xvfsp);
2993 return (SYSCTL_OUT(req, &xvfsp, sizeof(xvfsp)));
2994 }
2995 return (EOPNOTSUPP);
2996 }
2997
2998 static SYSCTL_NODE(_vfs, VFS_GENERIC, generic, CTLFLAG_RD | CTLFLAG_SKIP,
2999 vfs_sysctl, "Generic filesystem");
3000
3001 #if 1 || defined(COMPAT_PRELITE2)
3002
3003 static int
3004 sysctl_ovfs_conf(SYSCTL_HANDLER_ARGS)
3005 {
3006 int error;
3007 struct vfsconf *vfsp;
3008 struct ovfsconf ovfs;
3009
3010 TAILQ_FOREACH(vfsp, &vfsconf, vfc_list) {
3011 bzero(&ovfs, sizeof(ovfs));
3012 ovfs.vfc_vfsops = vfsp->vfc_vfsops; /* XXX used as flag */
3013 strcpy(ovfs.vfc_name, vfsp->vfc_name);
3014 ovfs.vfc_index = vfsp->vfc_typenum;
3015 ovfs.vfc_refcount = vfsp->vfc_refcount;
3016 ovfs.vfc_flags = vfsp->vfc_flags;
3017 error = SYSCTL_OUT(req, &ovfs, sizeof ovfs);
3018 if (error)
3019 return error;
3020 }
3021 return 0;
3022 }
3023
3024 #endif /* 1 || COMPAT_PRELITE2 */
3025 #endif /* !BURN_BRIDGES */
3026
3027 #define KINFO_VNODESLOP 10
3028 #ifdef notyet
3029 /*
3030 * Dump vnode list (via sysctl).
3031 */
3032 /* ARGSUSED */
3033 static int
3034 sysctl_vnode(SYSCTL_HANDLER_ARGS)
3035 {
3036 struct xvnode *xvn;
3037 struct mount *mp;
3038 struct vnode *vp;
3039 int error, len, n;
3040
3041 /*
3042 * Stale numvnodes access is not fatal here.
3043 */
3044 req->lock = 0;
3045 len = (numvnodes + KINFO_VNODESLOP) * sizeof *xvn;
3046 if (!req->oldptr)
3047 /* Make an estimate */
3048 return (SYSCTL_OUT(req, 0, len));
3049
3050 error = sysctl_wire_old_buffer(req, 0);
3051 if (error != 0)
3052 return (error);
3053 xvn = malloc(len, M_TEMP, M_ZERO | M_WAITOK);
3054 n = 0;
3055 mtx_lock(&mountlist_mtx);
3056 TAILQ_FOREACH(mp, &mountlist, mnt_list) {
3057 if (vfs_busy(mp, MBF_NOWAIT | MBF_MNTLSTLOCK))
3058 continue;
3059 MNT_ILOCK(mp);
3060 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) {
3061 if (n == len)
3062 break;
3063 vref(vp);
3064 xvn[n].xv_size = sizeof *xvn;
3065 xvn[n].xv_vnode = vp;
3066 xvn[n].xv_id = 0; /* XXX compat */
3067 #define XV_COPY(field) xvn[n].xv_##field = vp->v_##field
3068 XV_COPY(usecount);
3069 XV_COPY(writecount);
3070 XV_COPY(holdcnt);
3071 XV_COPY(mount);
3072 XV_COPY(numoutput);
3073 XV_COPY(type);
3074 #undef XV_COPY
3075 xvn[n].xv_flag = vp->v_vflag;
3076
3077 switch (vp->v_type) {
3078 case VREG:
3079 case VDIR:
3080 case VLNK:
3081 break;
3082 case VBLK:
3083 case VCHR:
3084 if (vp->v_rdev == NULL) {
3085 vrele(vp);
3086 continue;
3087 }
3088 xvn[n].xv_dev = dev2udev(vp->v_rdev);
3089 break;
3090 case VSOCK:
3091 xvn[n].xv_socket = vp->v_socket;
3092 break;
3093 case VFIFO:
3094 xvn[n].xv_fifo = vp->v_fifoinfo;
3095 break;
3096 case VNON:
3097 case VBAD:
3098 default:
3099 /* shouldn't happen? */
3100 vrele(vp);
3101 continue;
3102 }
3103 vrele(vp);
3104 ++n;
3105 }
3106 MNT_IUNLOCK(mp);
3107 mtx_lock(&mountlist_mtx);
3108 vfs_unbusy(mp);
3109 if (n == len)
3110 break;
3111 }
3112 mtx_unlock(&mountlist_mtx);
3113
3114 error = SYSCTL_OUT(req, xvn, n * sizeof *xvn);
3115 free(xvn, M_TEMP);
3116 return (error);
3117 }
3118
3119 SYSCTL_PROC(_kern, KERN_VNODE, vnode, CTLTYPE_OPAQUE|CTLFLAG_RD,
3120 0, 0, sysctl_vnode, "S,xvnode", "");
3121 #endif
3122
3123 /*
3124 * Unmount all filesystems. The list is traversed in reverse order
3125 * of mounting to avoid dependencies.
3126 */
3127 void
3128 vfs_unmountall(void)
3129 {
3130 struct mount *mp;
3131 struct thread *td;
3132 int error;
3133
3134 KASSERT(curthread != NULL, ("vfs_unmountall: NULL curthread"));
3135 CTR1(KTR_VFS, "%s: unmounting all filesystems", __func__);
3136 td = curthread;
3137
3138 /*
3139 * Since this only runs when rebooting, it is not interlocked.
3140 */
3141 while(!TAILQ_EMPTY(&mountlist)) {
3142 mp = TAILQ_LAST(&mountlist, mntlist);
3143 error = dounmount(mp, MNT_FORCE, td);
3144 if (error) {
3145 TAILQ_REMOVE(&mountlist, mp, mnt_list);
3146 /*
3147 * XXX: Due to the way in which we mount the root
3148 * file system off of devfs, devfs will generate a
3149 * "busy" warning when we try to unmount it before
3150 * the root. Don't print a warning as a result in
3151 * order to avoid false positive errors that may
3152 * cause needless upset.
3153 */
3154 if (strcmp(mp->mnt_vfc->vfc_name, "devfs") != 0) {
3155 printf("unmount of %s failed (",
3156 mp->mnt_stat.f_mntonname);
3157 if (error == EBUSY)
3158 printf("BUSY)\n");
3159 else
3160 printf("%d)\n", error);
3161 }
3162 } else {
3163 /* The unmount has removed mp from the mountlist */
3164 }
3165 }
3166 }
3167
3168 /*
3169 * perform msync on all vnodes under a mount point
3170 * the mount point must be locked.
3171 */
3172 void
3173 vfs_msync(struct mount *mp, int flags)
3174 {
3175 struct vnode *vp, *mvp;
3176 struct vm_object *obj;
3177
3178 CTR2(KTR_VFS, "%s: mp %p", __func__, mp);
3179 MNT_ILOCK(mp);
3180 MNT_VNODE_FOREACH(vp, mp, mvp) {
3181 VI_LOCK(vp);
3182 obj = vp->v_object;
3183 if (obj != NULL && (obj->flags & OBJ_MIGHTBEDIRTY) != 0 &&
3184 (flags == MNT_WAIT || VOP_ISLOCKED(vp) == 0)) {
3185 MNT_IUNLOCK(mp);
3186 if (!vget(vp,
3187 LK_EXCLUSIVE | LK_RETRY | LK_INTERLOCK,
3188 curthread)) {
3189 if (vp->v_vflag & VV_NOSYNC) { /* unlinked */
3190 vput(vp);
3191 MNT_ILOCK(mp);
3192 continue;
3193 }
3194
3195 obj = vp->v_object;
3196 if (obj != NULL) {
3197 VM_OBJECT_LOCK(obj);
3198 vm_object_page_clean(obj, 0, 0,
3199 flags == MNT_WAIT ?
3200 OBJPC_SYNC : OBJPC_NOSYNC);
3201 VM_OBJECT_UNLOCK(obj);
3202 }
3203 vput(vp);
3204 }
3205 MNT_ILOCK(mp);
3206 } else
3207 VI_UNLOCK(vp);
3208 }
3209 MNT_IUNLOCK(mp);
3210 }
3211
3212 /*
3213 * Mark a vnode as free, putting it up for recycling.
3214 */
3215 static void
3216 vfree(struct vnode *vp)
3217 {
3218
3219 ASSERT_VI_LOCKED(vp, "vfree");
3220 mtx_lock(&vnode_free_list_mtx);
3221 VNASSERT(vp->v_op != NULL, vp, ("vfree: vnode already reclaimed."));
3222 VNASSERT((vp->v_iflag & VI_FREE) == 0, vp, ("vnode already free"));
3223 VNASSERT(VSHOULDFREE(vp), vp, ("vfree: freeing when we shouldn't"));
3224 VNASSERT((vp->v_iflag & VI_DOOMED) == 0, vp,
3225 ("vfree: Freeing doomed vnode"));
3226 CTR2(KTR_VFS, "%s: vp %p", __func__, vp);
3227 if (vp->v_iflag & VI_AGE) {
3228 TAILQ_INSERT_HEAD(&vnode_free_list, vp, v_freelist);
3229 } else {
3230 TAILQ_INSERT_TAIL(&vnode_free_list, vp, v_freelist);
3231 }
3232 freevnodes++;
3233 vp->v_iflag &= ~VI_AGE;
3234 vp->v_iflag |= VI_FREE;
3235 mtx_unlock(&vnode_free_list_mtx);
3236 }
3237
3238 /*
3239 * Opposite of vfree() - mark a vnode as in use.
3240 */
3241 static void
3242 vbusy(struct vnode *vp)
3243 {
3244 ASSERT_VI_LOCKED(vp, "vbusy");
3245 VNASSERT((vp->v_iflag & VI_FREE) != 0, vp, ("vnode not free"));
3246 VNASSERT(vp->v_op != NULL, vp, ("vbusy: vnode already reclaimed."));
3247 CTR2(KTR_VFS, "%s: vp %p", __func__, vp);
3248
3249 mtx_lock(&vnode_free_list_mtx);
3250 TAILQ_REMOVE(&vnode_free_list, vp, v_freelist);
3251 freevnodes--;
3252 vp->v_iflag &= ~(VI_FREE|VI_AGE);
3253 mtx_unlock(&vnode_free_list_mtx);
3254 }
3255
3256 static void
3257 destroy_vpollinfo(struct vpollinfo *vi)
3258 {
3259 knlist_destroy(&vi->vpi_selinfo.si_note);
3260 mtx_destroy(&vi->vpi_lock);
3261 uma_zfree(vnodepoll_zone, vi);
3262 }
3263
3264 /*
3265 * Initalize per-vnode helper structure to hold poll-related state.
3266 */
3267 void
3268 v_addpollinfo(struct vnode *vp)
3269 {
3270 struct vpollinfo *vi;
3271
3272 if (vp->v_pollinfo != NULL)
3273 return;
3274 vi = uma_zalloc(vnodepoll_zone, M_WAITOK);
3275 mtx_init(&vi->vpi_lock, "vnode pollinfo", NULL, MTX_DEF);
3276 knlist_init(&vi->vpi_selinfo.si_note, vp, vfs_knllock,
3277 vfs_knlunlock, vfs_knl_assert_locked, vfs_knl_assert_unlocked);
3278 VI_LOCK(vp);
3279 if (vp->v_pollinfo != NULL) {
3280 VI_UNLOCK(vp);
3281 destroy_vpollinfo(vi);
3282 return;
3283 }
3284 vp->v_pollinfo = vi;
3285 VI_UNLOCK(vp);
3286 }
3287
3288 /*
3289 * Record a process's interest in events which might happen to
3290 * a vnode. Because poll uses the historic select-style interface
3291 * internally, this routine serves as both the ``check for any
3292 * pending events'' and the ``record my interest in future events''
3293 * functions. (These are done together, while the lock is held,
3294 * to avoid race conditions.)
3295 */
3296 int
3297 vn_pollrecord(struct vnode *vp, struct thread *td, int events)
3298 {
3299
3300 v_addpollinfo(vp);
3301 mtx_lock(&vp->v_pollinfo->vpi_lock);
3302 if (vp->v_pollinfo->vpi_revents & events) {
3303 /*
3304 * This leaves events we are not interested
3305 * in available for the other process which
3306 * which presumably had requested them
3307 * (otherwise they would never have been
3308 * recorded).
3309 */
3310 events &= vp->v_pollinfo->vpi_revents;
3311 vp->v_pollinfo->vpi_revents &= ~events;
3312
3313 mtx_unlock(&vp->v_pollinfo->vpi_lock);
3314 return (events);
3315 }
3316 vp->v_pollinfo->vpi_events |= events;
3317 selrecord(td, &vp->v_pollinfo->vpi_selinfo);
3318 mtx_unlock(&vp->v_pollinfo->vpi_lock);
3319 return (0);
3320 }
3321
3322 /*
3323 * Routine to create and manage a filesystem syncer vnode.
3324 */
3325 #define sync_close ((int (*)(struct vop_close_args *))nullop)
3326 static int sync_fsync(struct vop_fsync_args *);
3327 static int sync_inactive(struct vop_inactive_args *);
3328 static int sync_reclaim(struct vop_reclaim_args *);
3329
3330 static struct vop_vector sync_vnodeops = {
3331 .vop_bypass = VOP_EOPNOTSUPP,
3332 .vop_close = sync_close, /* close */
3333 .vop_fsync = sync_fsync, /* fsync */
3334 .vop_inactive = sync_inactive, /* inactive */
3335 .vop_reclaim = sync_reclaim, /* reclaim */
3336 .vop_lock1 = vop_stdlock, /* lock */
3337 .vop_unlock = vop_stdunlock, /* unlock */
3338 .vop_islocked = vop_stdislocked, /* islocked */
3339 };
3340
3341 /*
3342 * Create a new filesystem syncer vnode for the specified mount point.
3343 */
3344 int
3345 vfs_allocate_syncvnode(struct mount *mp)
3346 {
3347 struct vnode *vp;
3348 struct bufobj *bo;
3349 static long start, incr, next;
3350 int error;
3351
3352 /* Allocate a new vnode */
3353 if ((error = getnewvnode("syncer", mp, &sync_vnodeops, &vp)) != 0) {
3354 mp->mnt_syncer = NULL;
3355 return (error);
3356 }
3357 vp->v_type = VNON;
3358 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
3359 vp->v_vflag |= VV_FORCEINSMQ;
3360 error = insmntque(vp, mp);
3361 if (error != 0)
3362 panic("vfs_allocate_syncvnode: insmntque failed");
3363 vp->v_vflag &= ~VV_FORCEINSMQ;
3364 VOP_UNLOCK(vp, 0);
3365 /*
3366 * Place the vnode onto the syncer worklist. We attempt to
3367 * scatter them about on the list so that they will go off
3368 * at evenly distributed times even if all the filesystems
3369 * are mounted at once.
3370 */
3371 next += incr;
3372 if (next == 0 || next > syncer_maxdelay) {
3373 start /= 2;
3374 incr /= 2;
3375 if (start == 0) {
3376 start = syncer_maxdelay / 2;
3377 incr = syncer_maxdelay;
3378 }
3379 next = start;
3380 }
3381 bo = &vp->v_bufobj;
3382 BO_LOCK(bo);
3383 vn_syncer_add_to_worklist(bo, syncdelay > 0 ? next % syncdelay : 0);
3384 /* XXX - vn_syncer_add_to_worklist() also grabs and drops sync_mtx. */
3385 mtx_lock(&sync_mtx);
3386 sync_vnode_count++;
3387 mtx_unlock(&sync_mtx);
3388 BO_UNLOCK(bo);
3389 mp->mnt_syncer = vp;
3390 return (0);
3391 }
3392
3393 /*
3394 * Do a lazy sync of the filesystem.
3395 */
3396 static int
3397 sync_fsync(struct vop_fsync_args *ap)
3398 {
3399 struct vnode *syncvp = ap->a_vp;
3400 struct mount *mp = syncvp->v_mount;
3401 int error;
3402 struct bufobj *bo;
3403
3404 /*
3405 * We only need to do something if this is a lazy evaluation.
3406 */
3407 if (ap->a_waitfor != MNT_LAZY)
3408 return (0);
3409
3410 /*
3411 * Move ourselves to the back of the sync list.
3412 */
3413 bo = &syncvp->v_bufobj;
3414 BO_LOCK(bo);
3415 vn_syncer_add_to_worklist(bo, syncdelay);
3416 BO_UNLOCK(bo);
3417
3418 /*
3419 * Walk the list of vnodes pushing all that are dirty and
3420 * not already on the sync list.
3421 */
3422 mtx_lock(&mountlist_mtx);
3423 if (vfs_busy(mp, MBF_NOWAIT | MBF_MNTLSTLOCK) != 0) {
3424 mtx_unlock(&mountlist_mtx);
3425 return (0);
3426 }
3427 if (vn_start_write(NULL, &mp, V_NOWAIT) != 0) {
3428 vfs_unbusy(mp);
3429 return (0);
3430 }
3431 MNT_ILOCK(mp);
3432 mp->mnt_noasync++;
3433 mp->mnt_kern_flag &= ~MNTK_ASYNC;
3434 MNT_IUNLOCK(mp);
3435 vfs_msync(mp, MNT_NOWAIT);
3436 error = VFS_SYNC(mp, MNT_LAZY);
3437 MNT_ILOCK(mp);
3438 mp->mnt_noasync--;
3439 if ((mp->mnt_flag & MNT_ASYNC) != 0 && mp->mnt_noasync == 0)
3440 mp->mnt_kern_flag |= MNTK_ASYNC;
3441 MNT_IUNLOCK(mp);
3442 vn_finished_write(mp);
3443 vfs_unbusy(mp);
3444 return (error);
3445 }
3446
3447 /*
3448 * The syncer vnode is no referenced.
3449 */
3450 static int
3451 sync_inactive(struct vop_inactive_args *ap)
3452 {
3453
3454 vgone(ap->a_vp);
3455 return (0);
3456 }
3457
3458 /*
3459 * The syncer vnode is no longer needed and is being decommissioned.
3460 *
3461 * Modifications to the worklist must be protected by sync_mtx.
3462 */
3463 static int
3464 sync_reclaim(struct vop_reclaim_args *ap)
3465 {
3466 struct vnode *vp = ap->a_vp;
3467 struct bufobj *bo;
3468
3469 bo = &vp->v_bufobj;
3470 BO_LOCK(bo);
3471 vp->v_mount->mnt_syncer = NULL;
3472 if (bo->bo_flag & BO_ONWORKLST) {
3473 mtx_lock(&sync_mtx);
3474 LIST_REMOVE(bo, bo_synclist);
3475 syncer_worklist_len--;
3476 sync_vnode_count--;
3477 mtx_unlock(&sync_mtx);
3478 bo->bo_flag &= ~BO_ONWORKLST;
3479 }
3480 BO_UNLOCK(bo);
3481
3482 return (0);
3483 }
3484
3485 /*
3486 * Check if vnode represents a disk device
3487 */
3488 int
3489 vn_isdisk(struct vnode *vp, int *errp)
3490 {
3491 int error;
3492
3493 error = 0;
3494 dev_lock();
3495 if (vp->v_type != VCHR)
3496 error = ENOTBLK;
3497 else if (vp->v_rdev == NULL)
3498 error = ENXIO;
3499 else if (vp->v_rdev->si_devsw == NULL)
3500 error = ENXIO;
3501 else if (!(vp->v_rdev->si_devsw->d_flags & D_DISK))
3502 error = ENOTBLK;
3503 dev_unlock();
3504 if (errp != NULL)
3505 *errp = error;
3506 return (error == 0);
3507 }
3508
3509 /*
3510 * Common filesystem object access control check routine. Accepts a
3511 * vnode's type, "mode", uid and gid, requested access mode, credentials,
3512 * and optional call-by-reference privused argument allowing vaccess()
3513 * to indicate to the caller whether privilege was used to satisfy the
3514 * request (obsoleted). Returns 0 on success, or an errno on failure.
3515 *
3516 * The ifdef'd CAPABILITIES version is here for reference, but is not
3517 * actually used.
3518 */
3519 int
3520 vaccess(enum vtype type, mode_t file_mode, uid_t file_uid, gid_t file_gid,
3521 accmode_t accmode, struct ucred *cred, int *privused)
3522 {
3523 accmode_t dac_granted;
3524 accmode_t priv_granted;
3525
3526 KASSERT((accmode & ~(VEXEC | VWRITE | VREAD | VADMIN | VAPPEND)) == 0,
3527 ("invalid bit in accmode"));
3528
3529 /*
3530 * Look for a normal, non-privileged way to access the file/directory
3531 * as requested. If it exists, go with that.
3532 */
3533
3534 if (privused != NULL)
3535 *privused = 0;
3536
3537 dac_granted = 0;
3538
3539 /* Check the owner. */
3540 if (cred->cr_uid == file_uid) {
3541 dac_granted |= VADMIN;
3542 if (file_mode & S_IXUSR)
3543 dac_granted |= VEXEC;
3544 if (file_mode & S_IRUSR)
3545 dac_granted |= VREAD;
3546 if (file_mode & S_IWUSR)
3547 dac_granted |= (VWRITE | VAPPEND);
3548
3549 if ((accmode & dac_granted) == accmode)
3550 return (0);
3551
3552 goto privcheck;
3553 }
3554
3555 /* Otherwise, check the groups (first match) */
3556 if (groupmember(file_gid, cred)) {
3557 if (file_mode & S_IXGRP)
3558 dac_granted |= VEXEC;
3559 if (file_mode & S_IRGRP)
3560 dac_granted |= VREAD;
3561 if (file_mode & S_IWGRP)
3562 dac_granted |= (VWRITE | VAPPEND);
3563
3564 if ((accmode & dac_granted) == accmode)
3565 return (0);
3566
3567 goto privcheck;
3568 }
3569
3570 /* Otherwise, check everyone else. */
3571 if (file_mode & S_IXOTH)
3572 dac_granted |= VEXEC;
3573 if (file_mode & S_IROTH)
3574 dac_granted |= VREAD;
3575 if (file_mode & S_IWOTH)
3576 dac_granted |= (VWRITE | VAPPEND);
3577 if ((accmode & dac_granted) == accmode)
3578 return (0);
3579
3580 privcheck:
3581 /*
3582 * Build a privilege mask to determine if the set of privileges
3583 * satisfies the requirements when combined with the granted mask
3584 * from above. For each privilege, if the privilege is required,
3585 * bitwise or the request type onto the priv_granted mask.
3586 */
3587 priv_granted = 0;
3588
3589 if (type == VDIR) {
3590 /*
3591 * For directories, use PRIV_VFS_LOOKUP to satisfy VEXEC
3592 * requests, instead of PRIV_VFS_EXEC.
3593 */
3594 if ((accmode & VEXEC) && ((dac_granted & VEXEC) == 0) &&
3595 !priv_check_cred(cred, PRIV_VFS_LOOKUP, 0))
3596 priv_granted |= VEXEC;
3597 } else {
3598 if ((accmode & VEXEC) && ((dac_granted & VEXEC) == 0) &&
3599 !priv_check_cred(cred, PRIV_VFS_EXEC, 0))
3600 priv_granted |= VEXEC;
3601 }
3602
3603 if ((accmode & VREAD) && ((dac_granted & VREAD) == 0) &&
3604 !priv_check_cred(cred, PRIV_VFS_READ, 0))
3605 priv_granted |= VREAD;
3606
3607 if ((accmode & VWRITE) && ((dac_granted & VWRITE) == 0) &&
3608 !priv_check_cred(cred, PRIV_VFS_WRITE, 0))
3609 priv_granted |= (VWRITE | VAPPEND);
3610
3611 if ((accmode & VADMIN) && ((dac_granted & VADMIN) == 0) &&
3612 !priv_check_cred(cred, PRIV_VFS_ADMIN, 0))
3613 priv_granted |= VADMIN;
3614
3615 if ((accmode & (priv_granted | dac_granted)) == accmode) {
3616 /* XXX audit: privilege used */
3617 if (privused != NULL)
3618 *privused = 1;
3619 return (0);
3620 }
3621
3622 return ((accmode & VADMIN) ? EPERM : EACCES);
3623 }
3624
3625 /*
3626 * Credential check based on process requesting service, and per-attribute
3627 * permissions.
3628 */
3629 int
3630 extattr_check_cred(struct vnode *vp, int attrnamespace, struct ucred *cred,
3631 struct thread *td, accmode_t accmode)
3632 {
3633
3634 /*
3635 * Kernel-invoked always succeeds.
3636 */
3637 if (cred == NOCRED)
3638 return (0);
3639
3640 /*
3641 * Do not allow privileged processes in jail to directly manipulate
3642 * system attributes.
3643 */
3644 switch (attrnamespace) {
3645 case EXTATTR_NAMESPACE_SYSTEM:
3646 /* Potentially should be: return (EPERM); */
3647 return (priv_check_cred(cred, PRIV_VFS_EXTATTR_SYSTEM, 0));
3648 case EXTATTR_NAMESPACE_USER:
3649 return (VOP_ACCESS(vp, accmode, cred, td));
3650 default:
3651 return (EPERM);
3652 }
3653 }
3654
3655 #ifdef DEBUG_VFS_LOCKS
3656 /*
3657 * This only exists to supress warnings from unlocked specfs accesses. It is
3658 * no longer ok to have an unlocked VFS.
3659 */
3660 #define IGNORE_LOCK(vp) (panicstr != NULL || (vp) == NULL || \
3661 (vp)->v_type == VCHR || (vp)->v_type == VBAD)
3662
3663 int vfs_badlock_ddb = 1; /* Drop into debugger on violation. */
3664 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_ddb, CTLFLAG_RW, &vfs_badlock_ddb, 0, "");
3665
3666 int vfs_badlock_mutex = 1; /* Check for interlock across VOPs. */
3667 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_mutex, CTLFLAG_RW, &vfs_badlock_mutex, 0, "");
3668
3669 int vfs_badlock_print = 1; /* Print lock violations. */
3670 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_print, CTLFLAG_RW, &vfs_badlock_print, 0, "");
3671
3672 #ifdef KDB
3673 int vfs_badlock_backtrace = 1; /* Print backtrace at lock violations. */
3674 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_backtrace, CTLFLAG_RW, &vfs_badlock_backtrace, 0, "");
3675 #endif
3676
3677 static void
3678 vfs_badlock(const char *msg, const char *str, struct vnode *vp)
3679 {
3680
3681 #ifdef KDB
3682 if (vfs_badlock_backtrace)
3683 kdb_backtrace();
3684 #endif
3685 if (vfs_badlock_print)
3686 printf("%s: %p %s\n", str, (void *)vp, msg);
3687 if (vfs_badlock_ddb)
3688 kdb_enter(KDB_WHY_VFSLOCK, "lock violation");
3689 }
3690
3691 void
3692 assert_vi_locked(struct vnode *vp, const char *str)
3693 {
3694
3695 if (vfs_badlock_mutex && !mtx_owned(VI_MTX(vp)))
3696 vfs_badlock("interlock is not locked but should be", str, vp);
3697 }
3698
3699 void
3700 assert_vi_unlocked(struct vnode *vp, const char *str)
3701 {
3702
3703 if (vfs_badlock_mutex && mtx_owned(VI_MTX(vp)))
3704 vfs_badlock("interlock is locked but should not be", str, vp);
3705 }
3706
3707 void
3708 assert_vop_locked(struct vnode *vp, const char *str)
3709 {
3710
3711 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) == 0)
3712 vfs_badlock("is not locked but should be", str, vp);
3713 }
3714
3715 void
3716 assert_vop_unlocked(struct vnode *vp, const char *str)
3717 {
3718
3719 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) == LK_EXCLUSIVE)
3720 vfs_badlock("is locked but should not be", str, vp);
3721 }
3722
3723 void
3724 assert_vop_elocked(struct vnode *vp, const char *str)
3725 {
3726
3727 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) != LK_EXCLUSIVE)
3728 vfs_badlock("is not exclusive locked but should be", str, vp);
3729 }
3730
3731 #if 0
3732 void
3733 assert_vop_elocked_other(struct vnode *vp, const char *str)
3734 {
3735
3736 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) != LK_EXCLOTHER)
3737 vfs_badlock("is not exclusive locked by another thread",
3738 str, vp);
3739 }
3740
3741 void
3742 assert_vop_slocked(struct vnode *vp, const char *str)
3743 {
3744
3745 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) != LK_SHARED)
3746 vfs_badlock("is not locked shared but should be", str, vp);
3747 }
3748 #endif /* 0 */
3749 #endif /* DEBUG_VFS_LOCKS */
3750
3751 void
3752 vop_rename_fail(struct vop_rename_args *ap)
3753 {
3754
3755 if (ap->a_tvp != NULL)
3756 vput(ap->a_tvp);
3757 if (ap->a_tdvp == ap->a_tvp)
3758 vrele(ap->a_tdvp);
3759 else
3760 vput(ap->a_tdvp);
3761 vrele(ap->a_fdvp);
3762 vrele(ap->a_fvp);
3763 }
3764
3765 void
3766 vop_rename_pre(void *ap)
3767 {
3768 struct vop_rename_args *a = ap;
3769
3770 #ifdef DEBUG_VFS_LOCKS
3771 if (a->a_tvp)
3772 ASSERT_VI_UNLOCKED(a->a_tvp, "VOP_RENAME");
3773 ASSERT_VI_UNLOCKED(a->a_tdvp, "VOP_RENAME");
3774 ASSERT_VI_UNLOCKED(a->a_fvp, "VOP_RENAME");
3775 ASSERT_VI_UNLOCKED(a->a_fdvp, "VOP_RENAME");
3776
3777 /* Check the source (from). */
3778 if (a->a_tdvp != a->a_fdvp && a->a_tvp != a->a_fdvp)
3779 ASSERT_VOP_UNLOCKED(a->a_fdvp, "vop_rename: fdvp locked");
3780 if (a->a_tvp != a->a_fvp)
3781 ASSERT_VOP_UNLOCKED(a->a_fvp, "vop_rename: fvp locked");
3782
3783 /* Check the target. */
3784 if (a->a_tvp)
3785 ASSERT_VOP_LOCKED(a->a_tvp, "vop_rename: tvp not locked");
3786 ASSERT_VOP_LOCKED(a->a_tdvp, "vop_rename: tdvp not locked");
3787 #endif
3788 if (a->a_tdvp != a->a_fdvp)
3789 vhold(a->a_fdvp);
3790 if (a->a_tvp != a->a_fvp)
3791 vhold(a->a_fvp);
3792 vhold(a->a_tdvp);
3793 if (a->a_tvp)
3794 vhold(a->a_tvp);
3795 }
3796
3797 void
3798 vop_strategy_pre(void *ap)
3799 {
3800 #ifdef DEBUG_VFS_LOCKS
3801 struct vop_strategy_args *a;
3802 struct buf *bp;
3803
3804 a = ap;
3805 bp = a->a_bp;
3806
3807 /*
3808 * Cluster ops lock their component buffers but not the IO container.
3809 */
3810 if ((bp->b_flags & B_CLUSTER) != 0)
3811 return;
3812
3813 if (!BUF_ISLOCKED(bp)) {
3814 if (vfs_badlock_print)
3815 printf(
3816 "VOP_STRATEGY: bp is not locked but should be\n");
3817 if (vfs_badlock_ddb)
3818 kdb_enter(KDB_WHY_VFSLOCK, "lock violation");
3819 }
3820 #endif
3821 }
3822
3823 void
3824 vop_lookup_pre(void *ap)
3825 {
3826 #ifdef DEBUG_VFS_LOCKS
3827 struct vop_lookup_args *a;
3828 struct vnode *dvp;
3829
3830 a = ap;
3831 dvp = a->a_dvp;
3832 ASSERT_VI_UNLOCKED(dvp, "VOP_LOOKUP");
3833 ASSERT_VOP_LOCKED(dvp, "VOP_LOOKUP");
3834 #endif
3835 }
3836
3837 void
3838 vop_lookup_post(void *ap, int rc)
3839 {
3840 #ifdef DEBUG_VFS_LOCKS
3841 struct vop_lookup_args *a;
3842 struct vnode *dvp;
3843 struct vnode *vp;
3844
3845 a = ap;
3846 dvp = a->a_dvp;
3847 vp = *(a->a_vpp);
3848
3849 ASSERT_VI_UNLOCKED(dvp, "VOP_LOOKUP");
3850 ASSERT_VOP_LOCKED(dvp, "VOP_LOOKUP");
3851
3852 if (!rc)
3853 ASSERT_VOP_LOCKED(vp, "VOP_LOOKUP (child)");
3854 #endif
3855 }
3856
3857 void
3858 vop_lock_pre(void *ap)
3859 {
3860 #ifdef DEBUG_VFS_LOCKS
3861 struct vop_lock1_args *a = ap;
3862
3863 if ((a->a_flags & LK_INTERLOCK) == 0)
3864 ASSERT_VI_UNLOCKED(a->a_vp, "VOP_LOCK");
3865 else
3866 ASSERT_VI_LOCKED(a->a_vp, "VOP_LOCK");
3867 #endif
3868 }
3869
3870 void
3871 vop_lock_post(void *ap, int rc)
3872 {
3873 #ifdef DEBUG_VFS_LOCKS
3874 struct vop_lock1_args *a = ap;
3875
3876 ASSERT_VI_UNLOCKED(a->a_vp, "VOP_LOCK");
3877 if (rc == 0)
3878 ASSERT_VOP_LOCKED(a->a_vp, "VOP_LOCK");
3879 #endif
3880 }
3881
3882 void
3883 vop_unlock_pre(void *ap)
3884 {
3885 #ifdef DEBUG_VFS_LOCKS
3886 struct vop_unlock_args *a = ap;
3887
3888 if (a->a_flags & LK_INTERLOCK)
3889 ASSERT_VI_LOCKED(a->a_vp, "VOP_UNLOCK");
3890 ASSERT_VOP_LOCKED(a->a_vp, "VOP_UNLOCK");
3891 #endif
3892 }
3893
3894 void
3895 vop_unlock_post(void *ap, int rc)
3896 {
3897 #ifdef DEBUG_VFS_LOCKS
3898 struct vop_unlock_args *a = ap;
3899
3900 if (a->a_flags & LK_INTERLOCK)
3901 ASSERT_VI_UNLOCKED(a->a_vp, "VOP_UNLOCK");
3902 #endif
3903 }
3904
3905 void
3906 vop_create_post(void *ap, int rc)
3907 {
3908 struct vop_create_args *a = ap;
3909
3910 if (!rc)
3911 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE);
3912 }
3913
3914 void
3915 vop_link_post(void *ap, int rc)
3916 {
3917 struct vop_link_args *a = ap;
3918
3919 if (!rc) {
3920 VFS_KNOTE_LOCKED(a->a_vp, NOTE_LINK);
3921 VFS_KNOTE_LOCKED(a->a_tdvp, NOTE_WRITE);
3922 }
3923 }
3924
3925 void
3926 vop_mkdir_post(void *ap, int rc)
3927 {
3928 struct vop_mkdir_args *a = ap;
3929
3930 if (!rc)
3931 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE | NOTE_LINK);
3932 }
3933
3934 void
3935 vop_mknod_post(void *ap, int rc)
3936 {
3937 struct vop_mknod_args *a = ap;
3938
3939 if (!rc)
3940 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE);
3941 }
3942
3943 void
3944 vop_remove_post(void *ap, int rc)
3945 {
3946 struct vop_remove_args *a = ap;
3947
3948 if (!rc) {
3949 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE);
3950 VFS_KNOTE_LOCKED(a->a_vp, NOTE_DELETE);
3951 }
3952 }
3953
3954 void
3955 vop_rename_post(void *ap, int rc)
3956 {
3957 struct vop_rename_args *a = ap;
3958
3959 if (!rc) {
3960 VFS_KNOTE_UNLOCKED(a->a_fdvp, NOTE_WRITE);
3961 VFS_KNOTE_UNLOCKED(a->a_tdvp, NOTE_WRITE);
3962 VFS_KNOTE_UNLOCKED(a->a_fvp, NOTE_RENAME);
3963 if (a->a_tvp)
3964 VFS_KNOTE_UNLOCKED(a->a_tvp, NOTE_DELETE);
3965 }
3966 if (a->a_tdvp != a->a_fdvp)
3967 vdrop(a->a_fdvp);
3968 if (a->a_tvp != a->a_fvp)
3969 vdrop(a->a_fvp);
3970 vdrop(a->a_tdvp);
3971 if (a->a_tvp)
3972 vdrop(a->a_tvp);
3973 }
3974
3975 void
3976 vop_rmdir_post(void *ap, int rc)
3977 {
3978 struct vop_rmdir_args *a = ap;
3979
3980 if (!rc) {
3981 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE | NOTE_LINK);
3982 VFS_KNOTE_LOCKED(a->a_vp, NOTE_DELETE);
3983 }
3984 }
3985
3986 void
3987 vop_setattr_post(void *ap, int rc)
3988 {
3989 struct vop_setattr_args *a = ap;
3990
3991 if (!rc)
3992 VFS_KNOTE_LOCKED(a->a_vp, NOTE_ATTRIB);
3993 }
3994
3995 void
3996 vop_symlink_post(void *ap, int rc)
3997 {
3998 struct vop_symlink_args *a = ap;
3999
4000 if (!rc)
4001 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE);
4002 }
4003
4004 static struct knlist fs_knlist;
4005
4006 static void
4007 vfs_event_init(void *arg)
4008 {
4009 knlist_init_mtx(&fs_knlist, NULL);
4010 }
4011 /* XXX - correct order? */
4012 SYSINIT(vfs_knlist, SI_SUB_VFS, SI_ORDER_ANY, vfs_event_init, NULL);
4013
4014 void
4015 vfs_event_signal(fsid_t *fsid, u_int32_t event, intptr_t data __unused)
4016 {
4017
4018 KNOTE_UNLOCKED(&fs_knlist, event);
4019 }
4020
4021 static int filt_fsattach(struct knote *kn);
4022 static void filt_fsdetach(struct knote *kn);
4023 static int filt_fsevent(struct knote *kn, long hint);
4024
4025 struct filterops fs_filtops =
4026 { 0, filt_fsattach, filt_fsdetach, filt_fsevent };
4027
4028 static int
4029 filt_fsattach(struct knote *kn)
4030 {
4031
4032 kn->kn_flags |= EV_CLEAR;
4033 knlist_add(&fs_knlist, kn, 0);
4034 return (0);
4035 }
4036
4037 static void
4038 filt_fsdetach(struct knote *kn)
4039 {
4040
4041 knlist_remove(&fs_knlist, kn, 0);
4042 }
4043
4044 static int
4045 filt_fsevent(struct knote *kn, long hint)
4046 {
4047
4048 kn->kn_fflags |= hint;
4049 return (kn->kn_fflags != 0);
4050 }
4051
4052 static int
4053 sysctl_vfs_ctl(SYSCTL_HANDLER_ARGS)
4054 {
4055 struct vfsidctl vc;
4056 int error;
4057 struct mount *mp;
4058
4059 error = SYSCTL_IN(req, &vc, sizeof(vc));
4060 if (error)
4061 return (error);
4062 if (vc.vc_vers != VFS_CTL_VERS1)
4063 return (EINVAL);
4064 mp = vfs_getvfs(&vc.vc_fsid);
4065 if (mp == NULL)
4066 return (ENOENT);
4067 /* ensure that a specific sysctl goes to the right filesystem. */
4068 if (strcmp(vc.vc_fstypename, "*") != 0 &&
4069 strcmp(vc.vc_fstypename, mp->mnt_vfc->vfc_name) != 0) {
4070 vfs_rel(mp);
4071 return (EINVAL);
4072 }
4073 VCTLTOREQ(&vc, req);
4074 error = VFS_SYSCTL(mp, vc.vc_op, req);
4075 vfs_rel(mp);
4076 return (error);
4077 }
4078
4079 SYSCTL_PROC(_vfs, OID_AUTO, ctl, CTLFLAG_WR, NULL, 0, sysctl_vfs_ctl, "",
4080 "Sysctl by fsid");
4081
4082 /*
4083 * Function to initialize a va_filerev field sensibly.
4084 * XXX: Wouldn't a random number make a lot more sense ??
4085 */
4086 u_quad_t
4087 init_va_filerev(void)
4088 {
4089 struct bintime bt;
4090
4091 getbinuptime(&bt);
4092 return (((u_quad_t)bt.sec << 32LL) | (bt.frac >> 32LL));
4093 }
4094
4095 static int filt_vfsread(struct knote *kn, long hint);
4096 static int filt_vfswrite(struct knote *kn, long hint);
4097 static int filt_vfsvnode(struct knote *kn, long hint);
4098 static void filt_vfsdetach(struct knote *kn);
4099 static struct filterops vfsread_filtops =
4100 { 1, NULL, filt_vfsdetach, filt_vfsread };
4101 static struct filterops vfswrite_filtops =
4102 { 1, NULL, filt_vfsdetach, filt_vfswrite };
4103 static struct filterops vfsvnode_filtops =
4104 { 1, NULL, filt_vfsdetach, filt_vfsvnode };
4105
4106 static void
4107 vfs_knllock(void *arg)
4108 {
4109 struct vnode *vp = arg;
4110
4111 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
4112 }
4113
4114 static void
4115 vfs_knlunlock(void *arg)
4116 {
4117 struct vnode *vp = arg;
4118
4119 VOP_UNLOCK(vp, 0);
4120 }
4121
4122 static void
4123 vfs_knl_assert_locked(void *arg)
4124 {
4125 #ifdef DEBUG_VFS_LOCKS
4126 struct vnode *vp = arg;
4127
4128 ASSERT_VOP_LOCKED(vp, "vfs_knl_assert_locked");
4129 #endif
4130 }
4131
4132 static void
4133 vfs_knl_assert_unlocked(void *arg)
4134 {
4135 #ifdef DEBUG_VFS_LOCKS
4136 struct vnode *vp = arg;
4137
4138 ASSERT_VOP_UNLOCKED(vp, "vfs_knl_assert_unlocked");
4139 #endif
4140 }
4141
4142 int
4143 vfs_kqfilter(struct vop_kqfilter_args *ap)
4144 {
4145 struct vnode *vp = ap->a_vp;
4146 struct knote *kn = ap->a_kn;
4147 struct knlist *knl;
4148
4149 switch (kn->kn_filter) {
4150 case EVFILT_READ:
4151 kn->kn_fop = &vfsread_filtops;
4152 break;
4153 case EVFILT_WRITE:
4154 kn->kn_fop = &vfswrite_filtops;
4155 break;
4156 case EVFILT_VNODE:
4157 kn->kn_fop = &vfsvnode_filtops;
4158 break;
4159 default:
4160 return (EINVAL);
4161 }
4162
4163 kn->kn_hook = (caddr_t)vp;
4164
4165 v_addpollinfo(vp);
4166 if (vp->v_pollinfo == NULL)
4167 return (ENOMEM);
4168 knl = &vp->v_pollinfo->vpi_selinfo.si_note;
4169 knlist_add(knl, kn, 0);
4170
4171 return (0);
4172 }
4173
4174 /*
4175 * Detach knote from vnode
4176 */
4177 static void
4178 filt_vfsdetach(struct knote *kn)
4179 {
4180 struct vnode *vp = (struct vnode *)kn->kn_hook;
4181
4182 KASSERT(vp->v_pollinfo != NULL, ("Missing v_pollinfo"));
4183 knlist_remove(&vp->v_pollinfo->vpi_selinfo.si_note, kn, 0);
4184 }
4185
4186 /*ARGSUSED*/
4187 static int
4188 filt_vfsread(struct knote *kn, long hint)
4189 {
4190 struct vnode *vp = (struct vnode *)kn->kn_hook;
4191 struct vattr va;
4192 int res;
4193
4194 /*
4195 * filesystem is gone, so set the EOF flag and schedule
4196 * the knote for deletion.
4197 */
4198 if (hint == NOTE_REVOKE) {
4199 VI_LOCK(vp);
4200 kn->kn_flags |= (EV_EOF | EV_ONESHOT);
4201 VI_UNLOCK(vp);
4202 return (1);
4203 }
4204
4205 if (VOP_GETATTR(vp, &va, curthread->td_ucred))
4206 return (0);
4207
4208 VI_LOCK(vp);
4209 kn->kn_data = va.va_size - kn->kn_fp->f_offset;
4210 res = (kn->kn_data != 0);
4211 VI_UNLOCK(vp);
4212 return (res);
4213 }
4214
4215 /*ARGSUSED*/
4216 static int
4217 filt_vfswrite(struct knote *kn, long hint)
4218 {
4219 struct vnode *vp = (struct vnode *)kn->kn_hook;
4220
4221 VI_LOCK(vp);
4222
4223 /*
4224 * filesystem is gone, so set the EOF flag and schedule
4225 * the knote for deletion.
4226 */
4227 if (hint == NOTE_REVOKE)
4228 kn->kn_flags |= (EV_EOF | EV_ONESHOT);
4229
4230 kn->kn_data = 0;
4231 VI_UNLOCK(vp);
4232 return (1);
4233 }
4234
4235 static int
4236 filt_vfsvnode(struct knote *kn, long hint)
4237 {
4238 struct vnode *vp = (struct vnode *)kn->kn_hook;
4239 int res;
4240
4241 VI_LOCK(vp);
4242 if (kn->kn_sfflags & hint)
4243 kn->kn_fflags |= hint;
4244 if (hint == NOTE_REVOKE) {
4245 kn->kn_flags |= EV_EOF;
4246 VI_UNLOCK(vp);
4247 return (1);
4248 }
4249 res = (kn->kn_fflags != 0);
4250 VI_UNLOCK(vp);
4251 return (res);
4252 }
4253
4254 int
4255 vfs_read_dirent(struct vop_readdir_args *ap, struct dirent *dp, off_t off)
4256 {
4257 int error;
4258
4259 if (dp->d_reclen > ap->a_uio->uio_resid)
4260 return (ENAMETOOLONG);
4261 error = uiomove(dp, dp->d_reclen, ap->a_uio);
4262 if (error) {
4263 if (ap->a_ncookies != NULL) {
4264 if (ap->a_cookies != NULL)
4265 free(ap->a_cookies, M_TEMP);
4266 ap->a_cookies = NULL;
4267 *ap->a_ncookies = 0;
4268 }
4269 return (error);
4270 }
4271 if (ap->a_ncookies == NULL)
4272 return (0);
4273
4274 KASSERT(ap->a_cookies,
4275 ("NULL ap->a_cookies value with non-NULL ap->a_ncookies!"));
4276
4277 *ap->a_cookies = realloc(*ap->a_cookies,
4278 (*ap->a_ncookies + 1) * sizeof(u_long), M_TEMP, M_WAITOK | M_ZERO);
4279 (*ap->a_cookies)[*ap->a_ncookies] = off;
4280 return (0);
4281 }
4282
4283 /*
4284 * Mark for update the access time of the file if the filesystem
4285 * supports VOP_MARKATIME. This functionality is used by execve and
4286 * mmap, so we want to avoid the I/O implied by directly setting
4287 * va_atime for the sake of efficiency.
4288 */
4289 void
4290 vfs_mark_atime(struct vnode *vp, struct ucred *cred)
4291 {
4292 struct mount *mp;
4293
4294 mp = vp->v_mount;
4295 VFS_ASSERT_GIANT(mp);
4296 ASSERT_VOP_LOCKED(vp, "vfs_mark_atime");
4297 if (mp != NULL && (mp->mnt_flag & (MNT_NOATIME | MNT_RDONLY)) == 0)
4298 (void)VOP_MARKATIME(vp);
4299 }
4300
4301 /*
4302 * The purpose of this routine is to remove granularity from accmode_t,
4303 * reducing it into standard unix access bits - VEXEC, VREAD, VWRITE,
4304 * VADMIN and VAPPEND.
4305 *
4306 * If it returns 0, the caller is supposed to continue with the usual
4307 * access checks using 'accmode' as modified by this routine. If it
4308 * returns nonzero value, the caller is supposed to return that value
4309 * as errno.
4310 *
4311 * Note that after this routine runs, accmode may be zero.
4312 */
4313 int
4314 vfs_unixify_accmode(accmode_t *accmode)
4315 {
4316 /*
4317 * There is no way to specify explicit "deny" rule using
4318 * file mode or POSIX.1e ACLs.
4319 */
4320 if (*accmode & VEXPLICIT_DENY) {
4321 *accmode = 0;
4322 return (0);
4323 }
4324
4325 /*
4326 * None of these can be translated into usual access bits.
4327 * Also, the common case for NFSv4 ACLs is to not contain
4328 * either of these bits. Caller should check for VWRITE
4329 * on the containing directory instead.
4330 */
4331 if (*accmode & (VDELETE_CHILD | VDELETE))
4332 return (EPERM);
4333
4334 if (*accmode & VADMIN_PERMS) {
4335 *accmode &= ~VADMIN_PERMS;
4336 *accmode |= VADMIN;
4337 }
4338
4339 /*
4340 * There is no way to deny VREAD_ATTRIBUTES, VREAD_ACL
4341 * or VSYNCHRONIZE using file mode or POSIX.1e ACL.
4342 */
4343 *accmode &= ~(VSTAT_PERMS | VSYNCHRONIZE);
4344
4345 return (0);
4346 }
Cache object: 8936caeb1a90c2e5cd32587caba29f60
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