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/10.2/sys/kern/vfs_subr.c 284993 2015-07-01 06:54:25Z kib $");
43
44 #include "opt_compat.h"
45 #include "opt_ddb.h"
46 #include "opt_watchdog.h"
47
48 #include <sys/param.h>
49 #include <sys/systm.h>
50 #include <sys/bio.h>
51 #include <sys/buf.h>
52 #include <sys/condvar.h>
53 #include <sys/conf.h>
54 #include <sys/dirent.h>
55 #include <sys/event.h>
56 #include <sys/eventhandler.h>
57 #include <sys/extattr.h>
58 #include <sys/file.h>
59 #include <sys/fcntl.h>
60 #include <sys/jail.h>
61 #include <sys/kdb.h>
62 #include <sys/kernel.h>
63 #include <sys/kthread.h>
64 #include <sys/lockf.h>
65 #include <sys/malloc.h>
66 #include <sys/mount.h>
67 #include <sys/namei.h>
68 #include <sys/pctrie.h>
69 #include <sys/priv.h>
70 #include <sys/reboot.h>
71 #include <sys/rwlock.h>
72 #include <sys/sched.h>
73 #include <sys/sleepqueue.h>
74 #include <sys/smp.h>
75 #include <sys/stat.h>
76 #include <sys/sysctl.h>
77 #include <sys/syslog.h>
78 #include <sys/vmmeter.h>
79 #include <sys/vnode.h>
80 #include <sys/watchdog.h>
81
82 #include <machine/stdarg.h>
83
84 #include <security/mac/mac_framework.h>
85
86 #include <vm/vm.h>
87 #include <vm/vm_object.h>
88 #include <vm/vm_extern.h>
89 #include <vm/pmap.h>
90 #include <vm/vm_map.h>
91 #include <vm/vm_page.h>
92 #include <vm/vm_kern.h>
93 #include <vm/uma.h>
94
95 #ifdef DDB
96 #include <ddb/ddb.h>
97 #endif
98
99 static void delmntque(struct vnode *vp);
100 static int flushbuflist(struct bufv *bufv, int flags, struct bufobj *bo,
101 int slpflag, int slptimeo);
102 static void syncer_shutdown(void *arg, int howto);
103 static int vtryrecycle(struct vnode *vp);
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 vnlru_free(int);
109 static void vgonel(struct vnode *);
110 static void vfs_knllock(void *arg);
111 static void vfs_knlunlock(void *arg);
112 static void vfs_knl_assert_locked(void *arg);
113 static void vfs_knl_assert_unlocked(void *arg);
114 static void destroy_vpollinfo(struct vpollinfo *vi);
115
116 /*
117 * Number of vnodes in existence. Increased whenever getnewvnode()
118 * allocates a new vnode, decreased in vdropl() for VI_DOOMED vnode.
119 */
120 static unsigned long numvnodes;
121
122 SYSCTL_ULONG(_vfs, OID_AUTO, numvnodes, CTLFLAG_RD, &numvnodes, 0,
123 "Number of vnodes in existence");
124
125 static u_long vnodes_created;
126 SYSCTL_ULONG(_vfs, OID_AUTO, vnodes_created, CTLFLAG_RD, &vnodes_created,
127 0, "Number of vnodes created by getnewvnode");
128
129 /*
130 * Conversion tables for conversion from vnode types to inode formats
131 * and back.
132 */
133 enum vtype iftovt_tab[16] = {
134 VNON, VFIFO, VCHR, VNON, VDIR, VNON, VBLK, VNON,
135 VREG, VNON, VLNK, VNON, VSOCK, VNON, VNON, VBAD,
136 };
137 int vttoif_tab[10] = {
138 0, S_IFREG, S_IFDIR, S_IFBLK, S_IFCHR, S_IFLNK,
139 S_IFSOCK, S_IFIFO, S_IFMT, S_IFMT
140 };
141
142 /*
143 * List of vnodes that are ready for recycling.
144 */
145 static TAILQ_HEAD(freelst, vnode) vnode_free_list;
146
147 /*
148 * Free vnode target. Free vnodes may simply be files which have been stat'd
149 * but not read. This is somewhat common, and a small cache of such files
150 * should be kept to avoid recreation costs.
151 */
152 static u_long wantfreevnodes;
153 SYSCTL_ULONG(_vfs, OID_AUTO, wantfreevnodes, CTLFLAG_RW, &wantfreevnodes, 0, "");
154 /* Number of vnodes in the free list. */
155 static u_long freevnodes;
156 SYSCTL_ULONG(_vfs, OID_AUTO, freevnodes, CTLFLAG_RD, &freevnodes, 0,
157 "Number of vnodes in the free list");
158
159 static int vlru_allow_cache_src;
160 SYSCTL_INT(_vfs, OID_AUTO, vlru_allow_cache_src, CTLFLAG_RW,
161 &vlru_allow_cache_src, 0, "Allow vlru to reclaim source vnode");
162
163 static u_long recycles_count;
164 SYSCTL_ULONG(_vfs, OID_AUTO, recycles, CTLFLAG_RD, &recycles_count, 0,
165 "Number of vnodes recycled to avoid exceding kern.maxvnodes");
166
167 /*
168 * Various variables used for debugging the new implementation of
169 * reassignbuf().
170 * XXX these are probably of (very) limited utility now.
171 */
172 static int reassignbufcalls;
173 SYSCTL_INT(_vfs, OID_AUTO, reassignbufcalls, CTLFLAG_RW, &reassignbufcalls, 0,
174 "Number of calls to reassignbuf");
175
176 static u_long free_owe_inact;
177 SYSCTL_ULONG(_vfs, OID_AUTO, free_owe_inact, CTLFLAG_RD, &free_owe_inact, 0,
178 "Number of times free vnodes kept on active list due to VFS "
179 "owing inactivation");
180
181 /*
182 * Cache for the mount type id assigned to NFS. This is used for
183 * special checks in nfs/nfs_nqlease.c and vm/vnode_pager.c.
184 */
185 int nfs_mount_type = -1;
186
187 /* To keep more than one thread at a time from running vfs_getnewfsid */
188 static struct mtx mntid_mtx;
189
190 /*
191 * Lock for any access to the following:
192 * vnode_free_list
193 * numvnodes
194 * freevnodes
195 */
196 static struct mtx vnode_free_list_mtx;
197
198 /* Publicly exported FS */
199 struct nfs_public nfs_pub;
200
201 static uma_zone_t buf_trie_zone;
202
203 /* Zone for allocation of new vnodes - used exclusively by getnewvnode() */
204 static uma_zone_t vnode_zone;
205 static uma_zone_t vnodepoll_zone;
206
207 /*
208 * The workitem queue.
209 *
210 * It is useful to delay writes of file data and filesystem metadata
211 * for tens of seconds so that quickly created and deleted files need
212 * not waste disk bandwidth being created and removed. To realize this,
213 * we append vnodes to a "workitem" queue. When running with a soft
214 * updates implementation, most pending metadata dependencies should
215 * not wait for more than a few seconds. Thus, mounted on block devices
216 * are delayed only about a half the time that file data is delayed.
217 * Similarly, directory updates are more critical, so are only delayed
218 * about a third the time that file data is delayed. Thus, there are
219 * SYNCER_MAXDELAY queues that are processed round-robin at a rate of
220 * one each second (driven off the filesystem syncer process). The
221 * syncer_delayno variable indicates the next queue that is to be processed.
222 * Items that need to be processed soon are placed in this queue:
223 *
224 * syncer_workitem_pending[syncer_delayno]
225 *
226 * A delay of fifteen seconds is done by placing the request fifteen
227 * entries later in the queue:
228 *
229 * syncer_workitem_pending[(syncer_delayno + 15) & syncer_mask]
230 *
231 */
232 static int syncer_delayno;
233 static long syncer_mask;
234 LIST_HEAD(synclist, bufobj);
235 static struct synclist *syncer_workitem_pending;
236 /*
237 * The sync_mtx protects:
238 * bo->bo_synclist
239 * sync_vnode_count
240 * syncer_delayno
241 * syncer_state
242 * syncer_workitem_pending
243 * syncer_worklist_len
244 * rushjob
245 */
246 static struct mtx sync_mtx;
247 static struct cv sync_wakeup;
248
249 #define SYNCER_MAXDELAY 32
250 static int syncer_maxdelay = SYNCER_MAXDELAY; /* maximum delay time */
251 static int syncdelay = 30; /* max time to delay syncing data */
252 static int filedelay = 30; /* time to delay syncing files */
253 SYSCTL_INT(_kern, OID_AUTO, filedelay, CTLFLAG_RW, &filedelay, 0,
254 "Time to delay syncing files (in seconds)");
255 static int dirdelay = 29; /* time to delay syncing directories */
256 SYSCTL_INT(_kern, OID_AUTO, dirdelay, CTLFLAG_RW, &dirdelay, 0,
257 "Time to delay syncing directories (in seconds)");
258 static int metadelay = 28; /* time to delay syncing metadata */
259 SYSCTL_INT(_kern, OID_AUTO, metadelay, CTLFLAG_RW, &metadelay, 0,
260 "Time to delay syncing metadata (in seconds)");
261 static int rushjob; /* number of slots to run ASAP */
262 static int stat_rush_requests; /* number of times I/O speeded up */
263 SYSCTL_INT(_debug, OID_AUTO, rush_requests, CTLFLAG_RW, &stat_rush_requests, 0,
264 "Number of times I/O speeded up (rush requests)");
265
266 /*
267 * When shutting down the syncer, run it at four times normal speed.
268 */
269 #define SYNCER_SHUTDOWN_SPEEDUP 4
270 static int sync_vnode_count;
271 static int syncer_worklist_len;
272 static enum { SYNCER_RUNNING, SYNCER_SHUTTING_DOWN, SYNCER_FINAL_DELAY }
273 syncer_state;
274
275 /*
276 * Number of vnodes we want to exist at any one time. This is mostly used
277 * to size hash tables in vnode-related code. It is normally not used in
278 * getnewvnode(), as wantfreevnodes is normally nonzero.)
279 *
280 * XXX desiredvnodes is historical cruft and should not exist.
281 */
282 int desiredvnodes;
283 SYSCTL_INT(_kern, KERN_MAXVNODES, maxvnodes, CTLFLAG_RW,
284 &desiredvnodes, 0, "Maximum number of vnodes");
285 SYSCTL_ULONG(_kern, OID_AUTO, minvnodes, CTLFLAG_RW,
286 &wantfreevnodes, 0, "Minimum number of vnodes (legacy)");
287 static int vnlru_nowhere;
288 SYSCTL_INT(_debug, OID_AUTO, vnlru_nowhere, CTLFLAG_RW,
289 &vnlru_nowhere, 0, "Number of times the vnlru process ran without success");
290
291 /* Shift count for (uintptr_t)vp to initialize vp->v_hash. */
292 static int vnsz2log;
293
294 /*
295 * Support for the bufobj clean & dirty pctrie.
296 */
297 static void *
298 buf_trie_alloc(struct pctrie *ptree)
299 {
300
301 return uma_zalloc(buf_trie_zone, M_NOWAIT);
302 }
303
304 static void
305 buf_trie_free(struct pctrie *ptree, void *node)
306 {
307
308 uma_zfree(buf_trie_zone, node);
309 }
310 PCTRIE_DEFINE(BUF, buf, b_lblkno, buf_trie_alloc, buf_trie_free);
311
312 /*
313 * Initialize the vnode management data structures.
314 *
315 * Reevaluate the following cap on the number of vnodes after the physical
316 * memory size exceeds 512GB. In the limit, as the physical memory size
317 * grows, the ratio of physical pages to vnodes approaches sixteen to one.
318 */
319 #ifndef MAXVNODES_MAX
320 #define MAXVNODES_MAX (512 * (1024 * 1024 * 1024 / (int)PAGE_SIZE / 16))
321 #endif
322 static void
323 vntblinit(void *dummy __unused)
324 {
325 u_int i;
326 int physvnodes, virtvnodes;
327
328 /*
329 * Desiredvnodes is a function of the physical memory size and the
330 * kernel's heap size. Generally speaking, it scales with the
331 * physical memory size. The ratio of desiredvnodes to physical pages
332 * is one to four until desiredvnodes exceeds 98,304. Thereafter, the
333 * marginal ratio of desiredvnodes to physical pages is one to
334 * sixteen. However, desiredvnodes is limited by the kernel's heap
335 * size. The memory required by desiredvnodes vnodes and vm objects
336 * may not exceed one seventh of the kernel's heap size.
337 */
338 physvnodes = maxproc + cnt.v_page_count / 16 + 3 * min(98304 * 4,
339 cnt.v_page_count) / 16;
340 virtvnodes = vm_kmem_size / (7 * (sizeof(struct vm_object) +
341 sizeof(struct vnode)));
342 desiredvnodes = min(physvnodes, virtvnodes);
343 if (desiredvnodes > MAXVNODES_MAX) {
344 if (bootverbose)
345 printf("Reducing kern.maxvnodes %d -> %d\n",
346 desiredvnodes, MAXVNODES_MAX);
347 desiredvnodes = MAXVNODES_MAX;
348 }
349 wantfreevnodes = desiredvnodes / 4;
350 mtx_init(&mntid_mtx, "mntid", NULL, MTX_DEF);
351 TAILQ_INIT(&vnode_free_list);
352 mtx_init(&vnode_free_list_mtx, "vnode_free_list", NULL, MTX_DEF);
353 vnode_zone = uma_zcreate("VNODE", sizeof (struct vnode), NULL, NULL,
354 NULL, NULL, UMA_ALIGN_PTR, 0);
355 vnodepoll_zone = uma_zcreate("VNODEPOLL", sizeof (struct vpollinfo),
356 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0);
357 /*
358 * Preallocate enough nodes to support one-per buf so that
359 * we can not fail an insert. reassignbuf() callers can not
360 * tolerate the insertion failure.
361 */
362 buf_trie_zone = uma_zcreate("BUF TRIE", pctrie_node_size(),
363 NULL, NULL, pctrie_zone_init, NULL, UMA_ALIGN_PTR,
364 UMA_ZONE_NOFREE | UMA_ZONE_VM);
365 uma_prealloc(buf_trie_zone, nbuf);
366 /*
367 * Initialize the filesystem syncer.
368 */
369 syncer_workitem_pending = hashinit(syncer_maxdelay, M_VNODE,
370 &syncer_mask);
371 syncer_maxdelay = syncer_mask + 1;
372 mtx_init(&sync_mtx, "Syncer mtx", NULL, MTX_DEF);
373 cv_init(&sync_wakeup, "syncer");
374 for (i = 1; i <= sizeof(struct vnode); i <<= 1)
375 vnsz2log++;
376 vnsz2log--;
377 }
378 SYSINIT(vfs, SI_SUB_VFS, SI_ORDER_FIRST, vntblinit, NULL);
379
380
381 /*
382 * Mark a mount point as busy. Used to synchronize access and to delay
383 * unmounting. Eventually, mountlist_mtx is not released on failure.
384 *
385 * vfs_busy() is a custom lock, it can block the caller.
386 * vfs_busy() only sleeps if the unmount is active on the mount point.
387 * For a mountpoint mp, vfs_busy-enforced lock is before lock of any
388 * vnode belonging to mp.
389 *
390 * Lookup uses vfs_busy() to traverse mount points.
391 * root fs var fs
392 * / vnode lock A / vnode lock (/var) D
393 * /var vnode lock B /log vnode lock(/var/log) E
394 * vfs_busy lock C vfs_busy lock F
395 *
396 * Within each file system, the lock order is C->A->B and F->D->E.
397 *
398 * When traversing across mounts, the system follows that lock order:
399 *
400 * C->A->B
401 * |
402 * +->F->D->E
403 *
404 * The lookup() process for namei("/var") illustrates the process:
405 * VOP_LOOKUP() obtains B while A is held
406 * vfs_busy() obtains a shared lock on F while A and B are held
407 * vput() releases lock on B
408 * vput() releases lock on A
409 * VFS_ROOT() obtains lock on D while shared lock on F is held
410 * vfs_unbusy() releases shared lock on F
411 * vn_lock() obtains lock on deadfs vnode vp_crossmp instead of A.
412 * Attempt to lock A (instead of vp_crossmp) while D is held would
413 * violate the global order, causing deadlocks.
414 *
415 * dounmount() locks B while F is drained.
416 */
417 int
418 vfs_busy(struct mount *mp, int flags)
419 {
420
421 MPASS((flags & ~MBF_MASK) == 0);
422 CTR3(KTR_VFS, "%s: mp %p with flags %d", __func__, mp, flags);
423
424 MNT_ILOCK(mp);
425 MNT_REF(mp);
426 /*
427 * If mount point is currenly being unmounted, sleep until the
428 * mount point fate is decided. If thread doing the unmounting fails,
429 * it will clear MNTK_UNMOUNT flag before waking us up, indicating
430 * that this mount point has survived the unmount attempt and vfs_busy
431 * should retry. Otherwise the unmounter thread will set MNTK_REFEXPIRE
432 * flag in addition to MNTK_UNMOUNT, indicating that mount point is
433 * about to be really destroyed. vfs_busy needs to release its
434 * reference on the mount point in this case and return with ENOENT,
435 * telling the caller that mount mount it tried to busy is no longer
436 * valid.
437 */
438 while (mp->mnt_kern_flag & MNTK_UNMOUNT) {
439 if (flags & MBF_NOWAIT || mp->mnt_kern_flag & MNTK_REFEXPIRE) {
440 MNT_REL(mp);
441 MNT_IUNLOCK(mp);
442 CTR1(KTR_VFS, "%s: failed busying before sleeping",
443 __func__);
444 return (ENOENT);
445 }
446 if (flags & MBF_MNTLSTLOCK)
447 mtx_unlock(&mountlist_mtx);
448 mp->mnt_kern_flag |= MNTK_MWAIT;
449 msleep(mp, MNT_MTX(mp), PVFS | PDROP, "vfs_busy", 0);
450 if (flags & MBF_MNTLSTLOCK)
451 mtx_lock(&mountlist_mtx);
452 MNT_ILOCK(mp);
453 }
454 if (flags & MBF_MNTLSTLOCK)
455 mtx_unlock(&mountlist_mtx);
456 mp->mnt_lockref++;
457 MNT_IUNLOCK(mp);
458 return (0);
459 }
460
461 /*
462 * Free a busy filesystem.
463 */
464 void
465 vfs_unbusy(struct mount *mp)
466 {
467
468 CTR2(KTR_VFS, "%s: mp %p", __func__, mp);
469 MNT_ILOCK(mp);
470 MNT_REL(mp);
471 KASSERT(mp->mnt_lockref > 0, ("negative mnt_lockref"));
472 mp->mnt_lockref--;
473 if (mp->mnt_lockref == 0 && (mp->mnt_kern_flag & MNTK_DRAINING) != 0) {
474 MPASS(mp->mnt_kern_flag & MNTK_UNMOUNT);
475 CTR1(KTR_VFS, "%s: waking up waiters", __func__);
476 mp->mnt_kern_flag &= ~MNTK_DRAINING;
477 wakeup(&mp->mnt_lockref);
478 }
479 MNT_IUNLOCK(mp);
480 }
481
482 /*
483 * Lookup a mount point by filesystem identifier.
484 */
485 struct mount *
486 vfs_getvfs(fsid_t *fsid)
487 {
488 struct mount *mp;
489
490 CTR2(KTR_VFS, "%s: fsid %p", __func__, fsid);
491 mtx_lock(&mountlist_mtx);
492 TAILQ_FOREACH(mp, &mountlist, mnt_list) {
493 if (mp->mnt_stat.f_fsid.val[0] == fsid->val[0] &&
494 mp->mnt_stat.f_fsid.val[1] == fsid->val[1]) {
495 vfs_ref(mp);
496 mtx_unlock(&mountlist_mtx);
497 return (mp);
498 }
499 }
500 mtx_unlock(&mountlist_mtx);
501 CTR2(KTR_VFS, "%s: lookup failed for %p id", __func__, fsid);
502 return ((struct mount *) 0);
503 }
504
505 /*
506 * Lookup a mount point by filesystem identifier, busying it before
507 * returning.
508 *
509 * To avoid congestion on mountlist_mtx, implement simple direct-mapped
510 * cache for popular filesystem identifiers. The cache is lockess, using
511 * the fact that struct mount's are never freed. In worst case we may
512 * get pointer to unmounted or even different filesystem, so we have to
513 * check what we got, and go slow way if so.
514 */
515 struct mount *
516 vfs_busyfs(fsid_t *fsid)
517 {
518 #define FSID_CACHE_SIZE 256
519 typedef struct mount * volatile vmp_t;
520 static vmp_t cache[FSID_CACHE_SIZE];
521 struct mount *mp;
522 int error;
523 uint32_t hash;
524
525 CTR2(KTR_VFS, "%s: fsid %p", __func__, fsid);
526 hash = fsid->val[0] ^ fsid->val[1];
527 hash = (hash >> 16 ^ hash) & (FSID_CACHE_SIZE - 1);
528 mp = cache[hash];
529 if (mp == NULL ||
530 mp->mnt_stat.f_fsid.val[0] != fsid->val[0] ||
531 mp->mnt_stat.f_fsid.val[1] != fsid->val[1])
532 goto slow;
533 if (vfs_busy(mp, 0) != 0) {
534 cache[hash] = NULL;
535 goto slow;
536 }
537 if (mp->mnt_stat.f_fsid.val[0] == fsid->val[0] &&
538 mp->mnt_stat.f_fsid.val[1] == fsid->val[1])
539 return (mp);
540 else
541 vfs_unbusy(mp);
542
543 slow:
544 mtx_lock(&mountlist_mtx);
545 TAILQ_FOREACH(mp, &mountlist, mnt_list) {
546 if (mp->mnt_stat.f_fsid.val[0] == fsid->val[0] &&
547 mp->mnt_stat.f_fsid.val[1] == fsid->val[1]) {
548 error = vfs_busy(mp, MBF_MNTLSTLOCK);
549 if (error) {
550 cache[hash] = NULL;
551 mtx_unlock(&mountlist_mtx);
552 return (NULL);
553 }
554 cache[hash] = mp;
555 return (mp);
556 }
557 }
558 CTR2(KTR_VFS, "%s: lookup failed for %p id", __func__, fsid);
559 mtx_unlock(&mountlist_mtx);
560 return ((struct mount *) 0);
561 }
562
563 /*
564 * Check if a user can access privileged mount options.
565 */
566 int
567 vfs_suser(struct mount *mp, struct thread *td)
568 {
569 int error;
570
571 /*
572 * If the thread is jailed, but this is not a jail-friendly file
573 * system, deny immediately.
574 */
575 if (!(mp->mnt_vfc->vfc_flags & VFCF_JAIL) && jailed(td->td_ucred))
576 return (EPERM);
577
578 /*
579 * If the file system was mounted outside the jail of the calling
580 * thread, deny immediately.
581 */
582 if (prison_check(td->td_ucred, mp->mnt_cred) != 0)
583 return (EPERM);
584
585 /*
586 * If file system supports delegated administration, we don't check
587 * for the PRIV_VFS_MOUNT_OWNER privilege - it will be better verified
588 * by the file system itself.
589 * If this is not the user that did original mount, we check for
590 * the PRIV_VFS_MOUNT_OWNER privilege.
591 */
592 if (!(mp->mnt_vfc->vfc_flags & VFCF_DELEGADMIN) &&
593 mp->mnt_cred->cr_uid != td->td_ucred->cr_uid) {
594 if ((error = priv_check(td, PRIV_VFS_MOUNT_OWNER)) != 0)
595 return (error);
596 }
597 return (0);
598 }
599
600 /*
601 * Get a new unique fsid. Try to make its val[0] unique, since this value
602 * will be used to create fake device numbers for stat(). Also try (but
603 * not so hard) make its val[0] unique mod 2^16, since some emulators only
604 * support 16-bit device numbers. We end up with unique val[0]'s for the
605 * first 2^16 calls and unique val[0]'s mod 2^16 for the first 2^8 calls.
606 *
607 * Keep in mind that several mounts may be running in parallel. Starting
608 * the search one past where the previous search terminated is both a
609 * micro-optimization and a defense against returning the same fsid to
610 * different mounts.
611 */
612 void
613 vfs_getnewfsid(struct mount *mp)
614 {
615 static uint16_t mntid_base;
616 struct mount *nmp;
617 fsid_t tfsid;
618 int mtype;
619
620 CTR2(KTR_VFS, "%s: mp %p", __func__, mp);
621 mtx_lock(&mntid_mtx);
622 mtype = mp->mnt_vfc->vfc_typenum;
623 tfsid.val[1] = mtype;
624 mtype = (mtype & 0xFF) << 24;
625 for (;;) {
626 tfsid.val[0] = makedev(255,
627 mtype | ((mntid_base & 0xFF00) << 8) | (mntid_base & 0xFF));
628 mntid_base++;
629 if ((nmp = vfs_getvfs(&tfsid)) == NULL)
630 break;
631 vfs_rel(nmp);
632 }
633 mp->mnt_stat.f_fsid.val[0] = tfsid.val[0];
634 mp->mnt_stat.f_fsid.val[1] = tfsid.val[1];
635 mtx_unlock(&mntid_mtx);
636 }
637
638 /*
639 * Knob to control the precision of file timestamps:
640 *
641 * 0 = seconds only; nanoseconds zeroed.
642 * 1 = seconds and nanoseconds, accurate within 1/HZ.
643 * 2 = seconds and nanoseconds, truncated to microseconds.
644 * >=3 = seconds and nanoseconds, maximum precision.
645 */
646 enum { TSP_SEC, TSP_HZ, TSP_USEC, TSP_NSEC };
647
648 static int timestamp_precision = TSP_USEC;
649 SYSCTL_INT(_vfs, OID_AUTO, timestamp_precision, CTLFLAG_RW,
650 ×tamp_precision, 0, "File timestamp precision (0: seconds, "
651 "1: sec + ns accurate to 1/HZ, 2: sec + ns truncated to ms, "
652 "3+: sec + ns (max. precision))");
653
654 /*
655 * Get a current timestamp.
656 */
657 void
658 vfs_timestamp(struct timespec *tsp)
659 {
660 struct timeval tv;
661
662 switch (timestamp_precision) {
663 case TSP_SEC:
664 tsp->tv_sec = time_second;
665 tsp->tv_nsec = 0;
666 break;
667 case TSP_HZ:
668 getnanotime(tsp);
669 break;
670 case TSP_USEC:
671 microtime(&tv);
672 TIMEVAL_TO_TIMESPEC(&tv, tsp);
673 break;
674 case TSP_NSEC:
675 default:
676 nanotime(tsp);
677 break;
678 }
679 }
680
681 /*
682 * Set vnode attributes to VNOVAL
683 */
684 void
685 vattr_null(struct vattr *vap)
686 {
687
688 vap->va_type = VNON;
689 vap->va_size = VNOVAL;
690 vap->va_bytes = VNOVAL;
691 vap->va_mode = VNOVAL;
692 vap->va_nlink = VNOVAL;
693 vap->va_uid = VNOVAL;
694 vap->va_gid = VNOVAL;
695 vap->va_fsid = VNOVAL;
696 vap->va_fileid = VNOVAL;
697 vap->va_blocksize = VNOVAL;
698 vap->va_rdev = VNOVAL;
699 vap->va_atime.tv_sec = VNOVAL;
700 vap->va_atime.tv_nsec = VNOVAL;
701 vap->va_mtime.tv_sec = VNOVAL;
702 vap->va_mtime.tv_nsec = VNOVAL;
703 vap->va_ctime.tv_sec = VNOVAL;
704 vap->va_ctime.tv_nsec = VNOVAL;
705 vap->va_birthtime.tv_sec = VNOVAL;
706 vap->va_birthtime.tv_nsec = VNOVAL;
707 vap->va_flags = VNOVAL;
708 vap->va_gen = VNOVAL;
709 vap->va_vaflags = 0;
710 }
711
712 /*
713 * This routine is called when we have too many vnodes. It attempts
714 * to free <count> vnodes and will potentially free vnodes that still
715 * have VM backing store (VM backing store is typically the cause
716 * of a vnode blowout so we want to do this). Therefore, this operation
717 * is not considered cheap.
718 *
719 * A number of conditions may prevent a vnode from being reclaimed.
720 * the buffer cache may have references on the vnode, a directory
721 * vnode may still have references due to the namei cache representing
722 * underlying files, or the vnode may be in active use. It is not
723 * desireable to reuse such vnodes. These conditions may cause the
724 * number of vnodes to reach some minimum value regardless of what
725 * you set kern.maxvnodes to. Do not set kern.maxvnodes too low.
726 */
727 static int
728 vlrureclaim(struct mount *mp)
729 {
730 struct vnode *vp;
731 int done;
732 int trigger;
733 int usevnodes;
734 int count;
735
736 /*
737 * Calculate the trigger point, don't allow user
738 * screwups to blow us up. This prevents us from
739 * recycling vnodes with lots of resident pages. We
740 * aren't trying to free memory, we are trying to
741 * free vnodes.
742 */
743 usevnodes = desiredvnodes;
744 if (usevnodes <= 0)
745 usevnodes = 1;
746 trigger = cnt.v_page_count * 2 / usevnodes;
747 done = 0;
748 vn_start_write(NULL, &mp, V_WAIT);
749 MNT_ILOCK(mp);
750 count = mp->mnt_nvnodelistsize / 10 + 1;
751 while (count != 0) {
752 vp = TAILQ_FIRST(&mp->mnt_nvnodelist);
753 while (vp != NULL && vp->v_type == VMARKER)
754 vp = TAILQ_NEXT(vp, v_nmntvnodes);
755 if (vp == NULL)
756 break;
757 TAILQ_REMOVE(&mp->mnt_nvnodelist, vp, v_nmntvnodes);
758 TAILQ_INSERT_TAIL(&mp->mnt_nvnodelist, vp, v_nmntvnodes);
759 --count;
760 if (!VI_TRYLOCK(vp))
761 goto next_iter;
762 /*
763 * If it's been deconstructed already, it's still
764 * referenced, or it exceeds the trigger, skip it.
765 */
766 if (vp->v_usecount ||
767 (!vlru_allow_cache_src &&
768 !LIST_EMPTY(&(vp)->v_cache_src)) ||
769 (vp->v_iflag & VI_DOOMED) != 0 || (vp->v_object != NULL &&
770 vp->v_object->resident_page_count > trigger)) {
771 VI_UNLOCK(vp);
772 goto next_iter;
773 }
774 MNT_IUNLOCK(mp);
775 vholdl(vp);
776 if (VOP_LOCK(vp, LK_INTERLOCK|LK_EXCLUSIVE|LK_NOWAIT)) {
777 vdrop(vp);
778 goto next_iter_mntunlocked;
779 }
780 VI_LOCK(vp);
781 /*
782 * v_usecount may have been bumped after VOP_LOCK() dropped
783 * the vnode interlock and before it was locked again.
784 *
785 * It is not necessary to recheck VI_DOOMED because it can
786 * only be set by another thread that holds both the vnode
787 * lock and vnode interlock. If another thread has the
788 * vnode lock before we get to VOP_LOCK() and obtains the
789 * vnode interlock after VOP_LOCK() drops the vnode
790 * interlock, the other thread will be unable to drop the
791 * vnode lock before our VOP_LOCK() call fails.
792 */
793 if (vp->v_usecount ||
794 (!vlru_allow_cache_src &&
795 !LIST_EMPTY(&(vp)->v_cache_src)) ||
796 (vp->v_object != NULL &&
797 vp->v_object->resident_page_count > trigger)) {
798 VOP_UNLOCK(vp, LK_INTERLOCK);
799 vdrop(vp);
800 goto next_iter_mntunlocked;
801 }
802 KASSERT((vp->v_iflag & VI_DOOMED) == 0,
803 ("VI_DOOMED unexpectedly detected in vlrureclaim()"));
804 atomic_add_long(&recycles_count, 1);
805 vgonel(vp);
806 VOP_UNLOCK(vp, 0);
807 vdropl(vp);
808 done++;
809 next_iter_mntunlocked:
810 if (!should_yield())
811 goto relock_mnt;
812 goto yield;
813 next_iter:
814 if (!should_yield())
815 continue;
816 MNT_IUNLOCK(mp);
817 yield:
818 kern_yield(PRI_USER);
819 relock_mnt:
820 MNT_ILOCK(mp);
821 }
822 MNT_IUNLOCK(mp);
823 vn_finished_write(mp);
824 return done;
825 }
826
827 /*
828 * Attempt to keep the free list at wantfreevnodes length.
829 */
830 static void
831 vnlru_free(int count)
832 {
833 struct vnode *vp;
834
835 mtx_assert(&vnode_free_list_mtx, MA_OWNED);
836 for (; count > 0; count--) {
837 vp = TAILQ_FIRST(&vnode_free_list);
838 /*
839 * The list can be modified while the free_list_mtx
840 * has been dropped and vp could be NULL here.
841 */
842 if (!vp)
843 break;
844 VNASSERT(vp->v_op != NULL, vp,
845 ("vnlru_free: vnode already reclaimed."));
846 KASSERT((vp->v_iflag & VI_FREE) != 0,
847 ("Removing vnode not on freelist"));
848 KASSERT((vp->v_iflag & VI_ACTIVE) == 0,
849 ("Mangling active vnode"));
850 TAILQ_REMOVE(&vnode_free_list, vp, v_actfreelist);
851 /*
852 * Don't recycle if we can't get the interlock.
853 */
854 if (!VI_TRYLOCK(vp)) {
855 TAILQ_INSERT_TAIL(&vnode_free_list, vp, v_actfreelist);
856 continue;
857 }
858 VNASSERT((vp->v_iflag & VI_FREE) != 0 && vp->v_holdcnt == 0,
859 vp, ("vp inconsistent on freelist"));
860
861 /*
862 * The clear of VI_FREE prevents activation of the
863 * vnode. There is no sense in putting the vnode on
864 * the mount point active list, only to remove it
865 * later during recycling. Inline the relevant part
866 * of vholdl(), to avoid triggering assertions or
867 * activating.
868 */
869 freevnodes--;
870 vp->v_iflag &= ~VI_FREE;
871 vp->v_holdcnt++;
872
873 mtx_unlock(&vnode_free_list_mtx);
874 VI_UNLOCK(vp);
875 vtryrecycle(vp);
876 /*
877 * If the recycled succeeded this vdrop will actually free
878 * the vnode. If not it will simply place it back on
879 * the free list.
880 */
881 vdrop(vp);
882 mtx_lock(&vnode_free_list_mtx);
883 }
884 }
885 /*
886 * Attempt to recycle vnodes in a context that is always safe to block.
887 * Calling vlrurecycle() from the bowels of filesystem code has some
888 * interesting deadlock problems.
889 */
890 static struct proc *vnlruproc;
891 static int vnlruproc_sig;
892
893 static void
894 vnlru_proc(void)
895 {
896 struct mount *mp, *nmp;
897 int done;
898 struct proc *p = vnlruproc;
899
900 EVENTHANDLER_REGISTER(shutdown_pre_sync, kproc_shutdown, p,
901 SHUTDOWN_PRI_FIRST);
902
903 for (;;) {
904 kproc_suspend_check(p);
905 mtx_lock(&vnode_free_list_mtx);
906 if (freevnodes > wantfreevnodes)
907 vnlru_free(freevnodes - wantfreevnodes);
908 if (numvnodes <= desiredvnodes * 9 / 10) {
909 vnlruproc_sig = 0;
910 wakeup(&vnlruproc_sig);
911 msleep(vnlruproc, &vnode_free_list_mtx,
912 PVFS|PDROP, "vlruwt", hz);
913 continue;
914 }
915 mtx_unlock(&vnode_free_list_mtx);
916 done = 0;
917 mtx_lock(&mountlist_mtx);
918 for (mp = TAILQ_FIRST(&mountlist); mp != NULL; mp = nmp) {
919 if (vfs_busy(mp, MBF_NOWAIT | MBF_MNTLSTLOCK)) {
920 nmp = TAILQ_NEXT(mp, mnt_list);
921 continue;
922 }
923 done += vlrureclaim(mp);
924 mtx_lock(&mountlist_mtx);
925 nmp = TAILQ_NEXT(mp, mnt_list);
926 vfs_unbusy(mp);
927 }
928 mtx_unlock(&mountlist_mtx);
929 if (done == 0) {
930 #if 0
931 /* These messages are temporary debugging aids */
932 if (vnlru_nowhere < 5)
933 printf("vnlru process getting nowhere..\n");
934 else if (vnlru_nowhere == 5)
935 printf("vnlru process messages stopped.\n");
936 #endif
937 vnlru_nowhere++;
938 tsleep(vnlruproc, PPAUSE, "vlrup", hz * 3);
939 } else
940 kern_yield(PRI_USER);
941 }
942 }
943
944 static struct kproc_desc vnlru_kp = {
945 "vnlru",
946 vnlru_proc,
947 &vnlruproc
948 };
949 SYSINIT(vnlru, SI_SUB_KTHREAD_UPDATE, SI_ORDER_FIRST, kproc_start,
950 &vnlru_kp);
951
952 /*
953 * Routines having to do with the management of the vnode table.
954 */
955
956 /*
957 * Try to recycle a freed vnode. We abort if anyone picks up a reference
958 * before we actually vgone(). This function must be called with the vnode
959 * held to prevent the vnode from being returned to the free list midway
960 * through vgone().
961 */
962 static int
963 vtryrecycle(struct vnode *vp)
964 {
965 struct mount *vnmp;
966
967 CTR2(KTR_VFS, "%s: vp %p", __func__, vp);
968 VNASSERT(vp->v_holdcnt, vp,
969 ("vtryrecycle: Recycling vp %p without a reference.", vp));
970 /*
971 * This vnode may found and locked via some other list, if so we
972 * can't recycle it yet.
973 */
974 if (VOP_LOCK(vp, LK_EXCLUSIVE | LK_NOWAIT) != 0) {
975 CTR2(KTR_VFS,
976 "%s: impossible to recycle, vp %p lock is already held",
977 __func__, vp);
978 return (EWOULDBLOCK);
979 }
980 /*
981 * Don't recycle if its filesystem is being suspended.
982 */
983 if (vn_start_write(vp, &vnmp, V_NOWAIT) != 0) {
984 VOP_UNLOCK(vp, 0);
985 CTR2(KTR_VFS,
986 "%s: impossible to recycle, cannot start the write for %p",
987 __func__, vp);
988 return (EBUSY);
989 }
990 /*
991 * If we got this far, we need to acquire the interlock and see if
992 * anyone picked up this vnode from another list. If not, we will
993 * mark it with DOOMED via vgonel() so that anyone who does find it
994 * will skip over it.
995 */
996 VI_LOCK(vp);
997 if (vp->v_usecount) {
998 VOP_UNLOCK(vp, LK_INTERLOCK);
999 vn_finished_write(vnmp);
1000 CTR2(KTR_VFS,
1001 "%s: impossible to recycle, %p is already referenced",
1002 __func__, vp);
1003 return (EBUSY);
1004 }
1005 if ((vp->v_iflag & VI_DOOMED) == 0) {
1006 atomic_add_long(&recycles_count, 1);
1007 vgonel(vp);
1008 }
1009 VOP_UNLOCK(vp, LK_INTERLOCK);
1010 vn_finished_write(vnmp);
1011 return (0);
1012 }
1013
1014 /*
1015 * Wait for available vnodes.
1016 */
1017 static int
1018 getnewvnode_wait(int suspended)
1019 {
1020
1021 mtx_assert(&vnode_free_list_mtx, MA_OWNED);
1022 if (numvnodes > desiredvnodes) {
1023 if (suspended) {
1024 /*
1025 * File system is beeing suspended, we cannot risk a
1026 * deadlock here, so allocate new vnode anyway.
1027 */
1028 if (freevnodes > wantfreevnodes)
1029 vnlru_free(freevnodes - wantfreevnodes);
1030 return (0);
1031 }
1032 if (vnlruproc_sig == 0) {
1033 vnlruproc_sig = 1; /* avoid unnecessary wakeups */
1034 wakeup(vnlruproc);
1035 }
1036 msleep(&vnlruproc_sig, &vnode_free_list_mtx, PVFS,
1037 "vlruwk", hz);
1038 }
1039 return (numvnodes > desiredvnodes ? ENFILE : 0);
1040 }
1041
1042 void
1043 getnewvnode_reserve(u_int count)
1044 {
1045 struct thread *td;
1046
1047 td = curthread;
1048 /* First try to be quick and racy. */
1049 if (atomic_fetchadd_long(&numvnodes, count) + count <= desiredvnodes) {
1050 td->td_vp_reserv += count;
1051 return;
1052 } else
1053 atomic_subtract_long(&numvnodes, count);
1054
1055 mtx_lock(&vnode_free_list_mtx);
1056 while (count > 0) {
1057 if (getnewvnode_wait(0) == 0) {
1058 count--;
1059 td->td_vp_reserv++;
1060 atomic_add_long(&numvnodes, 1);
1061 }
1062 }
1063 mtx_unlock(&vnode_free_list_mtx);
1064 }
1065
1066 void
1067 getnewvnode_drop_reserve(void)
1068 {
1069 struct thread *td;
1070
1071 td = curthread;
1072 atomic_subtract_long(&numvnodes, td->td_vp_reserv);
1073 td->td_vp_reserv = 0;
1074 }
1075
1076 /*
1077 * Return the next vnode from the free list.
1078 */
1079 int
1080 getnewvnode(const char *tag, struct mount *mp, struct vop_vector *vops,
1081 struct vnode **vpp)
1082 {
1083 struct vnode *vp;
1084 struct bufobj *bo;
1085 struct thread *td;
1086 int error;
1087
1088 CTR3(KTR_VFS, "%s: mp %p with tag %s", __func__, mp, tag);
1089 vp = NULL;
1090 td = curthread;
1091 if (td->td_vp_reserv > 0) {
1092 td->td_vp_reserv -= 1;
1093 goto alloc;
1094 }
1095 mtx_lock(&vnode_free_list_mtx);
1096 /*
1097 * Lend our context to reclaim vnodes if they've exceeded the max.
1098 */
1099 if (freevnodes > wantfreevnodes)
1100 vnlru_free(1);
1101 error = getnewvnode_wait(mp != NULL && (mp->mnt_kern_flag &
1102 MNTK_SUSPEND));
1103 #if 0 /* XXX Not all VFS_VGET/ffs_vget callers check returns. */
1104 if (error != 0) {
1105 mtx_unlock(&vnode_free_list_mtx);
1106 return (error);
1107 }
1108 #endif
1109 atomic_add_long(&numvnodes, 1);
1110 mtx_unlock(&vnode_free_list_mtx);
1111 alloc:
1112 atomic_add_long(&vnodes_created, 1);
1113 vp = (struct vnode *) uma_zalloc(vnode_zone, M_WAITOK|M_ZERO);
1114 /*
1115 * Setup locks.
1116 */
1117 vp->v_vnlock = &vp->v_lock;
1118 mtx_init(&vp->v_interlock, "vnode interlock", NULL, MTX_DEF);
1119 /*
1120 * By default, don't allow shared locks unless filesystems
1121 * opt-in.
1122 */
1123 lockinit(vp->v_vnlock, PVFS, tag, VLKTIMEOUT, LK_NOSHARE | LK_IS_VNODE);
1124 /*
1125 * Initialize bufobj.
1126 */
1127 bo = &vp->v_bufobj;
1128 bo->__bo_vnode = vp;
1129 rw_init(BO_LOCKPTR(bo), "bufobj interlock");
1130 bo->bo_ops = &buf_ops_bio;
1131 bo->bo_private = vp;
1132 TAILQ_INIT(&bo->bo_clean.bv_hd);
1133 TAILQ_INIT(&bo->bo_dirty.bv_hd);
1134 /*
1135 * Initialize namecache.
1136 */
1137 LIST_INIT(&vp->v_cache_src);
1138 TAILQ_INIT(&vp->v_cache_dst);
1139 /*
1140 * Finalize various vnode identity bits.
1141 */
1142 vp->v_type = VNON;
1143 vp->v_tag = tag;
1144 vp->v_op = vops;
1145 v_incr_usecount(vp);
1146 vp->v_data = NULL;
1147 #ifdef MAC
1148 mac_vnode_init(vp);
1149 if (mp != NULL && (mp->mnt_flag & MNT_MULTILABEL) == 0)
1150 mac_vnode_associate_singlelabel(mp, vp);
1151 else if (mp == NULL && vops != &dead_vnodeops)
1152 printf("NULL mp in getnewvnode()\n");
1153 #endif
1154 if (mp != NULL) {
1155 bo->bo_bsize = mp->mnt_stat.f_iosize;
1156 if ((mp->mnt_kern_flag & MNTK_NOKNOTE) != 0)
1157 vp->v_vflag |= VV_NOKNOTE;
1158 }
1159 rangelock_init(&vp->v_rl);
1160
1161 /*
1162 * For the filesystems which do not use vfs_hash_insert(),
1163 * still initialize v_hash to have vfs_hash_index() useful.
1164 * E.g., nullfs uses vfs_hash_index() on the lower vnode for
1165 * its own hashing.
1166 */
1167 vp->v_hash = (uintptr_t)vp >> vnsz2log;
1168
1169 *vpp = vp;
1170 return (0);
1171 }
1172
1173 /*
1174 * Delete from old mount point vnode list, if on one.
1175 */
1176 static void
1177 delmntque(struct vnode *vp)
1178 {
1179 struct mount *mp;
1180 int active;
1181
1182 mp = vp->v_mount;
1183 if (mp == NULL)
1184 return;
1185 MNT_ILOCK(mp);
1186 VI_LOCK(vp);
1187 KASSERT(mp->mnt_activevnodelistsize <= mp->mnt_nvnodelistsize,
1188 ("Active vnode list size %d > Vnode list size %d",
1189 mp->mnt_activevnodelistsize, mp->mnt_nvnodelistsize));
1190 active = vp->v_iflag & VI_ACTIVE;
1191 vp->v_iflag &= ~VI_ACTIVE;
1192 if (active) {
1193 mtx_lock(&vnode_free_list_mtx);
1194 TAILQ_REMOVE(&mp->mnt_activevnodelist, vp, v_actfreelist);
1195 mp->mnt_activevnodelistsize--;
1196 mtx_unlock(&vnode_free_list_mtx);
1197 }
1198 vp->v_mount = NULL;
1199 VI_UNLOCK(vp);
1200 VNASSERT(mp->mnt_nvnodelistsize > 0, vp,
1201 ("bad mount point vnode list size"));
1202 TAILQ_REMOVE(&mp->mnt_nvnodelist, vp, v_nmntvnodes);
1203 mp->mnt_nvnodelistsize--;
1204 MNT_REL(mp);
1205 MNT_IUNLOCK(mp);
1206 }
1207
1208 static void
1209 insmntque_stddtr(struct vnode *vp, void *dtr_arg)
1210 {
1211
1212 vp->v_data = NULL;
1213 vp->v_op = &dead_vnodeops;
1214 vgone(vp);
1215 vput(vp);
1216 }
1217
1218 /*
1219 * Insert into list of vnodes for the new mount point, if available.
1220 */
1221 int
1222 insmntque1(struct vnode *vp, struct mount *mp,
1223 void (*dtr)(struct vnode *, void *), void *dtr_arg)
1224 {
1225
1226 KASSERT(vp->v_mount == NULL,
1227 ("insmntque: vnode already on per mount vnode list"));
1228 VNASSERT(mp != NULL, vp, ("Don't call insmntque(foo, NULL)"));
1229 ASSERT_VOP_ELOCKED(vp, "insmntque: non-locked vp");
1230
1231 /*
1232 * We acquire the vnode interlock early to ensure that the
1233 * vnode cannot be recycled by another process releasing a
1234 * holdcnt on it before we get it on both the vnode list
1235 * and the active vnode list. The mount mutex protects only
1236 * manipulation of the vnode list and the vnode freelist
1237 * mutex protects only manipulation of the active vnode list.
1238 * Hence the need to hold the vnode interlock throughout.
1239 */
1240 MNT_ILOCK(mp);
1241 VI_LOCK(vp);
1242 if (((mp->mnt_kern_flag & MNTK_NOINSMNTQ) != 0 &&
1243 ((mp->mnt_kern_flag & MNTK_UNMOUNTF) != 0 ||
1244 mp->mnt_nvnodelistsize == 0)) &&
1245 (vp->v_vflag & VV_FORCEINSMQ) == 0) {
1246 VI_UNLOCK(vp);
1247 MNT_IUNLOCK(mp);
1248 if (dtr != NULL)
1249 dtr(vp, dtr_arg);
1250 return (EBUSY);
1251 }
1252 vp->v_mount = mp;
1253 MNT_REF(mp);
1254 TAILQ_INSERT_TAIL(&mp->mnt_nvnodelist, vp, v_nmntvnodes);
1255 VNASSERT(mp->mnt_nvnodelistsize >= 0, vp,
1256 ("neg mount point vnode list size"));
1257 mp->mnt_nvnodelistsize++;
1258 KASSERT((vp->v_iflag & VI_ACTIVE) == 0,
1259 ("Activating already active vnode"));
1260 vp->v_iflag |= VI_ACTIVE;
1261 mtx_lock(&vnode_free_list_mtx);
1262 TAILQ_INSERT_HEAD(&mp->mnt_activevnodelist, vp, v_actfreelist);
1263 mp->mnt_activevnodelistsize++;
1264 mtx_unlock(&vnode_free_list_mtx);
1265 VI_UNLOCK(vp);
1266 MNT_IUNLOCK(mp);
1267 return (0);
1268 }
1269
1270 int
1271 insmntque(struct vnode *vp, struct mount *mp)
1272 {
1273
1274 return (insmntque1(vp, mp, insmntque_stddtr, NULL));
1275 }
1276
1277 /*
1278 * Flush out and invalidate all buffers associated with a bufobj
1279 * Called with the underlying object locked.
1280 */
1281 int
1282 bufobj_invalbuf(struct bufobj *bo, int flags, int slpflag, int slptimeo)
1283 {
1284 int error;
1285
1286 BO_LOCK(bo);
1287 if (flags & V_SAVE) {
1288 error = bufobj_wwait(bo, slpflag, slptimeo);
1289 if (error) {
1290 BO_UNLOCK(bo);
1291 return (error);
1292 }
1293 if (bo->bo_dirty.bv_cnt > 0) {
1294 BO_UNLOCK(bo);
1295 if ((error = BO_SYNC(bo, MNT_WAIT)) != 0)
1296 return (error);
1297 /*
1298 * XXX We could save a lock/unlock if this was only
1299 * enabled under INVARIANTS
1300 */
1301 BO_LOCK(bo);
1302 if (bo->bo_numoutput > 0 || bo->bo_dirty.bv_cnt > 0)
1303 panic("vinvalbuf: dirty bufs");
1304 }
1305 }
1306 /*
1307 * If you alter this loop please notice that interlock is dropped and
1308 * reacquired in flushbuflist. Special care is needed to ensure that
1309 * no race conditions occur from this.
1310 */
1311 do {
1312 error = flushbuflist(&bo->bo_clean,
1313 flags, bo, slpflag, slptimeo);
1314 if (error == 0 && !(flags & V_CLEANONLY))
1315 error = flushbuflist(&bo->bo_dirty,
1316 flags, bo, slpflag, slptimeo);
1317 if (error != 0 && error != EAGAIN) {
1318 BO_UNLOCK(bo);
1319 return (error);
1320 }
1321 } while (error != 0);
1322
1323 /*
1324 * Wait for I/O to complete. XXX needs cleaning up. The vnode can
1325 * have write I/O in-progress but if there is a VM object then the
1326 * VM object can also have read-I/O in-progress.
1327 */
1328 do {
1329 bufobj_wwait(bo, 0, 0);
1330 BO_UNLOCK(bo);
1331 if (bo->bo_object != NULL) {
1332 VM_OBJECT_WLOCK(bo->bo_object);
1333 vm_object_pip_wait(bo->bo_object, "bovlbx");
1334 VM_OBJECT_WUNLOCK(bo->bo_object);
1335 }
1336 BO_LOCK(bo);
1337 } while (bo->bo_numoutput > 0);
1338 BO_UNLOCK(bo);
1339
1340 /*
1341 * Destroy the copy in the VM cache, too.
1342 */
1343 if (bo->bo_object != NULL &&
1344 (flags & (V_ALT | V_NORMAL | V_CLEANONLY)) == 0) {
1345 VM_OBJECT_WLOCK(bo->bo_object);
1346 vm_object_page_remove(bo->bo_object, 0, 0, (flags & V_SAVE) ?
1347 OBJPR_CLEANONLY : 0);
1348 VM_OBJECT_WUNLOCK(bo->bo_object);
1349 }
1350
1351 #ifdef INVARIANTS
1352 BO_LOCK(bo);
1353 if ((flags & (V_ALT | V_NORMAL | V_CLEANONLY)) == 0 &&
1354 (bo->bo_dirty.bv_cnt > 0 || bo->bo_clean.bv_cnt > 0))
1355 panic("vinvalbuf: flush failed");
1356 BO_UNLOCK(bo);
1357 #endif
1358 return (0);
1359 }
1360
1361 /*
1362 * Flush out and invalidate all buffers associated with a vnode.
1363 * Called with the underlying object locked.
1364 */
1365 int
1366 vinvalbuf(struct vnode *vp, int flags, int slpflag, int slptimeo)
1367 {
1368
1369 CTR3(KTR_VFS, "%s: vp %p with flags %d", __func__, vp, flags);
1370 ASSERT_VOP_LOCKED(vp, "vinvalbuf");
1371 if (vp->v_object != NULL && vp->v_object->handle != vp)
1372 return (0);
1373 return (bufobj_invalbuf(&vp->v_bufobj, flags, slpflag, slptimeo));
1374 }
1375
1376 /*
1377 * Flush out buffers on the specified list.
1378 *
1379 */
1380 static int
1381 flushbuflist(struct bufv *bufv, int flags, struct bufobj *bo, int slpflag,
1382 int slptimeo)
1383 {
1384 struct buf *bp, *nbp;
1385 int retval, error;
1386 daddr_t lblkno;
1387 b_xflags_t xflags;
1388
1389 ASSERT_BO_WLOCKED(bo);
1390
1391 retval = 0;
1392 TAILQ_FOREACH_SAFE(bp, &bufv->bv_hd, b_bobufs, nbp) {
1393 if (((flags & V_NORMAL) && (bp->b_xflags & BX_ALTDATA)) ||
1394 ((flags & V_ALT) && (bp->b_xflags & BX_ALTDATA) == 0)) {
1395 continue;
1396 }
1397 lblkno = 0;
1398 xflags = 0;
1399 if (nbp != NULL) {
1400 lblkno = nbp->b_lblkno;
1401 xflags = nbp->b_xflags & (BX_VNDIRTY | BX_VNCLEAN);
1402 }
1403 retval = EAGAIN;
1404 error = BUF_TIMELOCK(bp,
1405 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK, BO_LOCKPTR(bo),
1406 "flushbuf", slpflag, slptimeo);
1407 if (error) {
1408 BO_LOCK(bo);
1409 return (error != ENOLCK ? error : EAGAIN);
1410 }
1411 KASSERT(bp->b_bufobj == bo,
1412 ("bp %p wrong b_bufobj %p should be %p",
1413 bp, bp->b_bufobj, bo));
1414 if (bp->b_bufobj != bo) { /* XXX: necessary ? */
1415 BUF_UNLOCK(bp);
1416 BO_LOCK(bo);
1417 return (EAGAIN);
1418 }
1419 /*
1420 * XXX Since there are no node locks for NFS, I
1421 * believe there is a slight chance that a delayed
1422 * write will occur while sleeping just above, so
1423 * check for it.
1424 */
1425 if (((bp->b_flags & (B_DELWRI | B_INVAL)) == B_DELWRI) &&
1426 (flags & V_SAVE)) {
1427 bremfree(bp);
1428 bp->b_flags |= B_ASYNC;
1429 bwrite(bp);
1430 BO_LOCK(bo);
1431 return (EAGAIN); /* XXX: why not loop ? */
1432 }
1433 bremfree(bp);
1434 bp->b_flags |= (B_INVAL | B_RELBUF);
1435 bp->b_flags &= ~B_ASYNC;
1436 brelse(bp);
1437 BO_LOCK(bo);
1438 if (nbp != NULL &&
1439 (nbp->b_bufobj != bo ||
1440 nbp->b_lblkno != lblkno ||
1441 (nbp->b_xflags & (BX_VNDIRTY | BX_VNCLEAN)) != xflags))
1442 break; /* nbp invalid */
1443 }
1444 return (retval);
1445 }
1446
1447 /*
1448 * Truncate a file's buffer and pages to a specified length. This
1449 * is in lieu of the old vinvalbuf mechanism, which performed unneeded
1450 * sync activity.
1451 */
1452 int
1453 vtruncbuf(struct vnode *vp, struct ucred *cred, off_t length, int blksize)
1454 {
1455 struct buf *bp, *nbp;
1456 int anyfreed;
1457 int trunclbn;
1458 struct bufobj *bo;
1459
1460 CTR5(KTR_VFS, "%s: vp %p with cred %p and block %d:%ju", __func__,
1461 vp, cred, blksize, (uintmax_t)length);
1462
1463 /*
1464 * Round up to the *next* lbn.
1465 */
1466 trunclbn = (length + blksize - 1) / blksize;
1467
1468 ASSERT_VOP_LOCKED(vp, "vtruncbuf");
1469 restart:
1470 bo = &vp->v_bufobj;
1471 BO_LOCK(bo);
1472 anyfreed = 1;
1473 for (;anyfreed;) {
1474 anyfreed = 0;
1475 TAILQ_FOREACH_SAFE(bp, &bo->bo_clean.bv_hd, b_bobufs, nbp) {
1476 if (bp->b_lblkno < trunclbn)
1477 continue;
1478 if (BUF_LOCK(bp,
1479 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK,
1480 BO_LOCKPTR(bo)) == ENOLCK)
1481 goto restart;
1482
1483 bremfree(bp);
1484 bp->b_flags |= (B_INVAL | B_RELBUF);
1485 bp->b_flags &= ~B_ASYNC;
1486 brelse(bp);
1487 anyfreed = 1;
1488
1489 BO_LOCK(bo);
1490 if (nbp != NULL &&
1491 (((nbp->b_xflags & BX_VNCLEAN) == 0) ||
1492 (nbp->b_vp != vp) ||
1493 (nbp->b_flags & B_DELWRI))) {
1494 BO_UNLOCK(bo);
1495 goto restart;
1496 }
1497 }
1498
1499 TAILQ_FOREACH_SAFE(bp, &bo->bo_dirty.bv_hd, b_bobufs, nbp) {
1500 if (bp->b_lblkno < trunclbn)
1501 continue;
1502 if (BUF_LOCK(bp,
1503 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK,
1504 BO_LOCKPTR(bo)) == ENOLCK)
1505 goto restart;
1506 bremfree(bp);
1507 bp->b_flags |= (B_INVAL | B_RELBUF);
1508 bp->b_flags &= ~B_ASYNC;
1509 brelse(bp);
1510 anyfreed = 1;
1511
1512 BO_LOCK(bo);
1513 if (nbp != NULL &&
1514 (((nbp->b_xflags & BX_VNDIRTY) == 0) ||
1515 (nbp->b_vp != vp) ||
1516 (nbp->b_flags & B_DELWRI) == 0)) {
1517 BO_UNLOCK(bo);
1518 goto restart;
1519 }
1520 }
1521 }
1522
1523 if (length > 0) {
1524 restartsync:
1525 TAILQ_FOREACH_SAFE(bp, &bo->bo_dirty.bv_hd, b_bobufs, nbp) {
1526 if (bp->b_lblkno > 0)
1527 continue;
1528 /*
1529 * Since we hold the vnode lock this should only
1530 * fail if we're racing with the buf daemon.
1531 */
1532 if (BUF_LOCK(bp,
1533 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK,
1534 BO_LOCKPTR(bo)) == ENOLCK) {
1535 goto restart;
1536 }
1537 VNASSERT((bp->b_flags & B_DELWRI), vp,
1538 ("buf(%p) on dirty queue without DELWRI", bp));
1539
1540 bremfree(bp);
1541 bawrite(bp);
1542 BO_LOCK(bo);
1543 goto restartsync;
1544 }
1545 }
1546
1547 bufobj_wwait(bo, 0, 0);
1548 BO_UNLOCK(bo);
1549 vnode_pager_setsize(vp, length);
1550
1551 return (0);
1552 }
1553
1554 static void
1555 buf_vlist_remove(struct buf *bp)
1556 {
1557 struct bufv *bv;
1558
1559 KASSERT(bp->b_bufobj != NULL, ("No b_bufobj %p", bp));
1560 ASSERT_BO_WLOCKED(bp->b_bufobj);
1561 KASSERT((bp->b_xflags & (BX_VNDIRTY|BX_VNCLEAN)) !=
1562 (BX_VNDIRTY|BX_VNCLEAN),
1563 ("buf_vlist_remove: Buf %p is on two lists", bp));
1564 if (bp->b_xflags & BX_VNDIRTY)
1565 bv = &bp->b_bufobj->bo_dirty;
1566 else
1567 bv = &bp->b_bufobj->bo_clean;
1568 BUF_PCTRIE_REMOVE(&bv->bv_root, bp->b_lblkno);
1569 TAILQ_REMOVE(&bv->bv_hd, bp, b_bobufs);
1570 bv->bv_cnt--;
1571 bp->b_xflags &= ~(BX_VNDIRTY | BX_VNCLEAN);
1572 }
1573
1574 /*
1575 * Add the buffer to the sorted clean or dirty block list.
1576 *
1577 * NOTE: xflags is passed as a constant, optimizing this inline function!
1578 */
1579 static void
1580 buf_vlist_add(struct buf *bp, struct bufobj *bo, b_xflags_t xflags)
1581 {
1582 struct bufv *bv;
1583 struct buf *n;
1584 int error;
1585
1586 ASSERT_BO_WLOCKED(bo);
1587 KASSERT((bo->bo_flag & BO_DEAD) == 0, ("dead bo %p", bo));
1588 KASSERT((bp->b_xflags & (BX_VNDIRTY|BX_VNCLEAN)) == 0,
1589 ("buf_vlist_add: Buf %p has existing xflags %d", bp, bp->b_xflags));
1590 bp->b_xflags |= xflags;
1591 if (xflags & BX_VNDIRTY)
1592 bv = &bo->bo_dirty;
1593 else
1594 bv = &bo->bo_clean;
1595
1596 /*
1597 * Keep the list ordered. Optimize empty list insertion. Assume
1598 * we tend to grow at the tail so lookup_le should usually be cheaper
1599 * than _ge.
1600 */
1601 if (bv->bv_cnt == 0 ||
1602 bp->b_lblkno > TAILQ_LAST(&bv->bv_hd, buflists)->b_lblkno)
1603 TAILQ_INSERT_TAIL(&bv->bv_hd, bp, b_bobufs);
1604 else if ((n = BUF_PCTRIE_LOOKUP_LE(&bv->bv_root, bp->b_lblkno)) == NULL)
1605 TAILQ_INSERT_HEAD(&bv->bv_hd, bp, b_bobufs);
1606 else
1607 TAILQ_INSERT_AFTER(&bv->bv_hd, n, bp, b_bobufs);
1608 error = BUF_PCTRIE_INSERT(&bv->bv_root, bp);
1609 if (error)
1610 panic("buf_vlist_add: Preallocated nodes insufficient.");
1611 bv->bv_cnt++;
1612 }
1613
1614 /*
1615 * Lookup a buffer using the splay tree. Note that we specifically avoid
1616 * shadow buffers used in background bitmap writes.
1617 *
1618 * This code isn't quite efficient as it could be because we are maintaining
1619 * two sorted lists and do not know which list the block resides in.
1620 *
1621 * During a "make buildworld" the desired buffer is found at one of
1622 * the roots more than 60% of the time. Thus, checking both roots
1623 * before performing either splay eliminates unnecessary splays on the
1624 * first tree splayed.
1625 */
1626 struct buf *
1627 gbincore(struct bufobj *bo, daddr_t lblkno)
1628 {
1629 struct buf *bp;
1630
1631 ASSERT_BO_LOCKED(bo);
1632 bp = BUF_PCTRIE_LOOKUP(&bo->bo_clean.bv_root, lblkno);
1633 if (bp != NULL)
1634 return (bp);
1635 return BUF_PCTRIE_LOOKUP(&bo->bo_dirty.bv_root, lblkno);
1636 }
1637
1638 /*
1639 * Associate a buffer with a vnode.
1640 */
1641 void
1642 bgetvp(struct vnode *vp, struct buf *bp)
1643 {
1644 struct bufobj *bo;
1645
1646 bo = &vp->v_bufobj;
1647 ASSERT_BO_WLOCKED(bo);
1648 VNASSERT(bp->b_vp == NULL, bp->b_vp, ("bgetvp: not free"));
1649
1650 CTR3(KTR_BUF, "bgetvp(%p) vp %p flags %X", bp, vp, bp->b_flags);
1651 VNASSERT((bp->b_xflags & (BX_VNDIRTY|BX_VNCLEAN)) == 0, vp,
1652 ("bgetvp: bp already attached! %p", bp));
1653
1654 vhold(vp);
1655 bp->b_vp = vp;
1656 bp->b_bufobj = bo;
1657 /*
1658 * Insert onto list for new vnode.
1659 */
1660 buf_vlist_add(bp, bo, BX_VNCLEAN);
1661 }
1662
1663 /*
1664 * Disassociate a buffer from a vnode.
1665 */
1666 void
1667 brelvp(struct buf *bp)
1668 {
1669 struct bufobj *bo;
1670 struct vnode *vp;
1671
1672 CTR3(KTR_BUF, "brelvp(%p) vp %p flags %X", bp, bp->b_vp, bp->b_flags);
1673 KASSERT(bp->b_vp != NULL, ("brelvp: NULL"));
1674
1675 /*
1676 * Delete from old vnode list, if on one.
1677 */
1678 vp = bp->b_vp; /* XXX */
1679 bo = bp->b_bufobj;
1680 BO_LOCK(bo);
1681 if (bp->b_xflags & (BX_VNDIRTY | BX_VNCLEAN))
1682 buf_vlist_remove(bp);
1683 else
1684 panic("brelvp: Buffer %p not on queue.", bp);
1685 if ((bo->bo_flag & BO_ONWORKLST) && bo->bo_dirty.bv_cnt == 0) {
1686 bo->bo_flag &= ~BO_ONWORKLST;
1687 mtx_lock(&sync_mtx);
1688 LIST_REMOVE(bo, bo_synclist);
1689 syncer_worklist_len--;
1690 mtx_unlock(&sync_mtx);
1691 }
1692 bp->b_vp = NULL;
1693 bp->b_bufobj = NULL;
1694 BO_UNLOCK(bo);
1695 vdrop(vp);
1696 }
1697
1698 /*
1699 * Add an item to the syncer work queue.
1700 */
1701 static void
1702 vn_syncer_add_to_worklist(struct bufobj *bo, int delay)
1703 {
1704 int slot;
1705
1706 ASSERT_BO_WLOCKED(bo);
1707
1708 mtx_lock(&sync_mtx);
1709 if (bo->bo_flag & BO_ONWORKLST)
1710 LIST_REMOVE(bo, bo_synclist);
1711 else {
1712 bo->bo_flag |= BO_ONWORKLST;
1713 syncer_worklist_len++;
1714 }
1715
1716 if (delay > syncer_maxdelay - 2)
1717 delay = syncer_maxdelay - 2;
1718 slot = (syncer_delayno + delay) & syncer_mask;
1719
1720 LIST_INSERT_HEAD(&syncer_workitem_pending[slot], bo, bo_synclist);
1721 mtx_unlock(&sync_mtx);
1722 }
1723
1724 static int
1725 sysctl_vfs_worklist_len(SYSCTL_HANDLER_ARGS)
1726 {
1727 int error, len;
1728
1729 mtx_lock(&sync_mtx);
1730 len = syncer_worklist_len - sync_vnode_count;
1731 mtx_unlock(&sync_mtx);
1732 error = SYSCTL_OUT(req, &len, sizeof(len));
1733 return (error);
1734 }
1735
1736 SYSCTL_PROC(_vfs, OID_AUTO, worklist_len, CTLTYPE_INT | CTLFLAG_RD, NULL, 0,
1737 sysctl_vfs_worklist_len, "I", "Syncer thread worklist length");
1738
1739 static struct proc *updateproc;
1740 static void sched_sync(void);
1741 static struct kproc_desc up_kp = {
1742 "syncer",
1743 sched_sync,
1744 &updateproc
1745 };
1746 SYSINIT(syncer, SI_SUB_KTHREAD_UPDATE, SI_ORDER_FIRST, kproc_start, &up_kp);
1747
1748 static int
1749 sync_vnode(struct synclist *slp, struct bufobj **bo, struct thread *td)
1750 {
1751 struct vnode *vp;
1752 struct mount *mp;
1753
1754 *bo = LIST_FIRST(slp);
1755 if (*bo == NULL)
1756 return (0);
1757 vp = (*bo)->__bo_vnode; /* XXX */
1758 if (VOP_ISLOCKED(vp) != 0 || VI_TRYLOCK(vp) == 0)
1759 return (1);
1760 /*
1761 * We use vhold in case the vnode does not
1762 * successfully sync. vhold prevents the vnode from
1763 * going away when we unlock the sync_mtx so that
1764 * we can acquire the vnode interlock.
1765 */
1766 vholdl(vp);
1767 mtx_unlock(&sync_mtx);
1768 VI_UNLOCK(vp);
1769 if (vn_start_write(vp, &mp, V_NOWAIT) != 0) {
1770 vdrop(vp);
1771 mtx_lock(&sync_mtx);
1772 return (*bo == LIST_FIRST(slp));
1773 }
1774 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
1775 (void) VOP_FSYNC(vp, MNT_LAZY, td);
1776 VOP_UNLOCK(vp, 0);
1777 vn_finished_write(mp);
1778 BO_LOCK(*bo);
1779 if (((*bo)->bo_flag & BO_ONWORKLST) != 0) {
1780 /*
1781 * Put us back on the worklist. The worklist
1782 * routine will remove us from our current
1783 * position and then add us back in at a later
1784 * position.
1785 */
1786 vn_syncer_add_to_worklist(*bo, syncdelay);
1787 }
1788 BO_UNLOCK(*bo);
1789 vdrop(vp);
1790 mtx_lock(&sync_mtx);
1791 return (0);
1792 }
1793
1794 static int first_printf = 1;
1795
1796 /*
1797 * System filesystem synchronizer daemon.
1798 */
1799 static void
1800 sched_sync(void)
1801 {
1802 struct synclist *next, *slp;
1803 struct bufobj *bo;
1804 long starttime;
1805 struct thread *td = curthread;
1806 int last_work_seen;
1807 int net_worklist_len;
1808 int syncer_final_iter;
1809 int error;
1810
1811 last_work_seen = 0;
1812 syncer_final_iter = 0;
1813 syncer_state = SYNCER_RUNNING;
1814 starttime = time_uptime;
1815 td->td_pflags |= TDP_NORUNNINGBUF;
1816
1817 EVENTHANDLER_REGISTER(shutdown_pre_sync, syncer_shutdown, td->td_proc,
1818 SHUTDOWN_PRI_LAST);
1819
1820 mtx_lock(&sync_mtx);
1821 for (;;) {
1822 if (syncer_state == SYNCER_FINAL_DELAY &&
1823 syncer_final_iter == 0) {
1824 mtx_unlock(&sync_mtx);
1825 kproc_suspend_check(td->td_proc);
1826 mtx_lock(&sync_mtx);
1827 }
1828 net_worklist_len = syncer_worklist_len - sync_vnode_count;
1829 if (syncer_state != SYNCER_RUNNING &&
1830 starttime != time_uptime) {
1831 if (first_printf) {
1832 printf("\nSyncing disks, vnodes remaining...");
1833 first_printf = 0;
1834 }
1835 printf("%d ", net_worklist_len);
1836 }
1837 starttime = time_uptime;
1838
1839 /*
1840 * Push files whose dirty time has expired. Be careful
1841 * of interrupt race on slp queue.
1842 *
1843 * Skip over empty worklist slots when shutting down.
1844 */
1845 do {
1846 slp = &syncer_workitem_pending[syncer_delayno];
1847 syncer_delayno += 1;
1848 if (syncer_delayno == syncer_maxdelay)
1849 syncer_delayno = 0;
1850 next = &syncer_workitem_pending[syncer_delayno];
1851 /*
1852 * If the worklist has wrapped since the
1853 * it was emptied of all but syncer vnodes,
1854 * switch to the FINAL_DELAY state and run
1855 * for one more second.
1856 */
1857 if (syncer_state == SYNCER_SHUTTING_DOWN &&
1858 net_worklist_len == 0 &&
1859 last_work_seen == syncer_delayno) {
1860 syncer_state = SYNCER_FINAL_DELAY;
1861 syncer_final_iter = SYNCER_SHUTDOWN_SPEEDUP;
1862 }
1863 } while (syncer_state != SYNCER_RUNNING && LIST_EMPTY(slp) &&
1864 syncer_worklist_len > 0);
1865
1866 /*
1867 * Keep track of the last time there was anything
1868 * on the worklist other than syncer vnodes.
1869 * Return to the SHUTTING_DOWN state if any
1870 * new work appears.
1871 */
1872 if (net_worklist_len > 0 || syncer_state == SYNCER_RUNNING)
1873 last_work_seen = syncer_delayno;
1874 if (net_worklist_len > 0 && syncer_state == SYNCER_FINAL_DELAY)
1875 syncer_state = SYNCER_SHUTTING_DOWN;
1876 while (!LIST_EMPTY(slp)) {
1877 error = sync_vnode(slp, &bo, td);
1878 if (error == 1) {
1879 LIST_REMOVE(bo, bo_synclist);
1880 LIST_INSERT_HEAD(next, bo, bo_synclist);
1881 continue;
1882 }
1883
1884 if (first_printf == 0)
1885 wdog_kern_pat(WD_LASTVAL);
1886
1887 }
1888 if (syncer_state == SYNCER_FINAL_DELAY && syncer_final_iter > 0)
1889 syncer_final_iter--;
1890 /*
1891 * The variable rushjob allows the kernel to speed up the
1892 * processing of the filesystem syncer process. A rushjob
1893 * value of N tells the filesystem syncer to process the next
1894 * N seconds worth of work on its queue ASAP. Currently rushjob
1895 * is used by the soft update code to speed up the filesystem
1896 * syncer process when the incore state is getting so far
1897 * ahead of the disk that the kernel memory pool is being
1898 * threatened with exhaustion.
1899 */
1900 if (rushjob > 0) {
1901 rushjob -= 1;
1902 continue;
1903 }
1904 /*
1905 * Just sleep for a short period of time between
1906 * iterations when shutting down to allow some I/O
1907 * to happen.
1908 *
1909 * If it has taken us less than a second to process the
1910 * current work, then wait. Otherwise start right over
1911 * again. We can still lose time if any single round
1912 * takes more than two seconds, but it does not really
1913 * matter as we are just trying to generally pace the
1914 * filesystem activity.
1915 */
1916 if (syncer_state != SYNCER_RUNNING ||
1917 time_uptime == starttime) {
1918 thread_lock(td);
1919 sched_prio(td, PPAUSE);
1920 thread_unlock(td);
1921 }
1922 if (syncer_state != SYNCER_RUNNING)
1923 cv_timedwait(&sync_wakeup, &sync_mtx,
1924 hz / SYNCER_SHUTDOWN_SPEEDUP);
1925 else if (time_uptime == starttime)
1926 cv_timedwait(&sync_wakeup, &sync_mtx, hz);
1927 }
1928 }
1929
1930 /*
1931 * Request the syncer daemon to speed up its work.
1932 * We never push it to speed up more than half of its
1933 * normal turn time, otherwise it could take over the cpu.
1934 */
1935 int
1936 speedup_syncer(void)
1937 {
1938 int ret = 0;
1939
1940 mtx_lock(&sync_mtx);
1941 if (rushjob < syncdelay / 2) {
1942 rushjob += 1;
1943 stat_rush_requests += 1;
1944 ret = 1;
1945 }
1946 mtx_unlock(&sync_mtx);
1947 cv_broadcast(&sync_wakeup);
1948 return (ret);
1949 }
1950
1951 /*
1952 * Tell the syncer to speed up its work and run though its work
1953 * list several times, then tell it to shut down.
1954 */
1955 static void
1956 syncer_shutdown(void *arg, int howto)
1957 {
1958
1959 if (howto & RB_NOSYNC)
1960 return;
1961 mtx_lock(&sync_mtx);
1962 syncer_state = SYNCER_SHUTTING_DOWN;
1963 rushjob = 0;
1964 mtx_unlock(&sync_mtx);
1965 cv_broadcast(&sync_wakeup);
1966 kproc_shutdown(arg, howto);
1967 }
1968
1969 void
1970 syncer_suspend(void)
1971 {
1972
1973 syncer_shutdown(updateproc, 0);
1974 }
1975
1976 void
1977 syncer_resume(void)
1978 {
1979
1980 mtx_lock(&sync_mtx);
1981 first_printf = 1;
1982 syncer_state = SYNCER_RUNNING;
1983 mtx_unlock(&sync_mtx);
1984 cv_broadcast(&sync_wakeup);
1985 kproc_resume(updateproc);
1986 }
1987
1988 /*
1989 * Reassign a buffer from one vnode to another.
1990 * Used to assign file specific control information
1991 * (indirect blocks) to the vnode to which they belong.
1992 */
1993 void
1994 reassignbuf(struct buf *bp)
1995 {
1996 struct vnode *vp;
1997 struct bufobj *bo;
1998 int delay;
1999 #ifdef INVARIANTS
2000 struct bufv *bv;
2001 #endif
2002
2003 vp = bp->b_vp;
2004 bo = bp->b_bufobj;
2005 ++reassignbufcalls;
2006
2007 CTR3(KTR_BUF, "reassignbuf(%p) vp %p flags %X",
2008 bp, bp->b_vp, bp->b_flags);
2009 /*
2010 * B_PAGING flagged buffers cannot be reassigned because their vp
2011 * is not fully linked in.
2012 */
2013 if (bp->b_flags & B_PAGING)
2014 panic("cannot reassign paging buffer");
2015
2016 /*
2017 * Delete from old vnode list, if on one.
2018 */
2019 BO_LOCK(bo);
2020 if (bp->b_xflags & (BX_VNDIRTY | BX_VNCLEAN))
2021 buf_vlist_remove(bp);
2022 else
2023 panic("reassignbuf: Buffer %p not on queue.", bp);
2024 /*
2025 * If dirty, put on list of dirty buffers; otherwise insert onto list
2026 * of clean buffers.
2027 */
2028 if (bp->b_flags & B_DELWRI) {
2029 if ((bo->bo_flag & BO_ONWORKLST) == 0) {
2030 switch (vp->v_type) {
2031 case VDIR:
2032 delay = dirdelay;
2033 break;
2034 case VCHR:
2035 delay = metadelay;
2036 break;
2037 default:
2038 delay = filedelay;
2039 }
2040 vn_syncer_add_to_worklist(bo, delay);
2041 }
2042 buf_vlist_add(bp, bo, BX_VNDIRTY);
2043 } else {
2044 buf_vlist_add(bp, bo, BX_VNCLEAN);
2045
2046 if ((bo->bo_flag & BO_ONWORKLST) && bo->bo_dirty.bv_cnt == 0) {
2047 mtx_lock(&sync_mtx);
2048 LIST_REMOVE(bo, bo_synclist);
2049 syncer_worklist_len--;
2050 mtx_unlock(&sync_mtx);
2051 bo->bo_flag &= ~BO_ONWORKLST;
2052 }
2053 }
2054 #ifdef INVARIANTS
2055 bv = &bo->bo_clean;
2056 bp = TAILQ_FIRST(&bv->bv_hd);
2057 KASSERT(bp == NULL || bp->b_bufobj == bo,
2058 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo));
2059 bp = TAILQ_LAST(&bv->bv_hd, buflists);
2060 KASSERT(bp == NULL || bp->b_bufobj == bo,
2061 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo));
2062 bv = &bo->bo_dirty;
2063 bp = TAILQ_FIRST(&bv->bv_hd);
2064 KASSERT(bp == NULL || bp->b_bufobj == bo,
2065 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo));
2066 bp = TAILQ_LAST(&bv->bv_hd, buflists);
2067 KASSERT(bp == NULL || bp->b_bufobj == bo,
2068 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo));
2069 #endif
2070 BO_UNLOCK(bo);
2071 }
2072
2073 /*
2074 * Increment the use and hold counts on the vnode, taking care to reference
2075 * the driver's usecount if this is a chardev. The vholdl() will remove
2076 * the vnode from the free list if it is presently free. Requires the
2077 * vnode interlock and returns with it held.
2078 */
2079 static void
2080 v_incr_usecount(struct vnode *vp)
2081 {
2082
2083 CTR2(KTR_VFS, "%s: vp %p", __func__, vp);
2084 vholdl(vp);
2085 vp->v_usecount++;
2086 if (vp->v_type == VCHR && vp->v_rdev != NULL) {
2087 dev_lock();
2088 vp->v_rdev->si_usecount++;
2089 dev_unlock();
2090 }
2091 }
2092
2093 /*
2094 * Turn a holdcnt into a use+holdcnt such that only one call to
2095 * v_decr_usecount is needed.
2096 */
2097 static void
2098 v_upgrade_usecount(struct vnode *vp)
2099 {
2100
2101 CTR2(KTR_VFS, "%s: vp %p", __func__, vp);
2102 vp->v_usecount++;
2103 if (vp->v_type == VCHR && vp->v_rdev != NULL) {
2104 dev_lock();
2105 vp->v_rdev->si_usecount++;
2106 dev_unlock();
2107 }
2108 }
2109
2110 /*
2111 * Decrement the vnode use and hold count along with the driver's usecount
2112 * if this is a chardev. The vdropl() below releases the vnode interlock
2113 * as it may free the vnode.
2114 */
2115 static void
2116 v_decr_usecount(struct vnode *vp)
2117 {
2118
2119 ASSERT_VI_LOCKED(vp, __FUNCTION__);
2120 VNASSERT(vp->v_usecount > 0, vp,
2121 ("v_decr_usecount: negative usecount"));
2122 CTR2(KTR_VFS, "%s: vp %p", __func__, vp);
2123 vp->v_usecount--;
2124 if (vp->v_type == VCHR && vp->v_rdev != NULL) {
2125 dev_lock();
2126 vp->v_rdev->si_usecount--;
2127 dev_unlock();
2128 }
2129 vdropl(vp);
2130 }
2131
2132 /*
2133 * Decrement only the use count and driver use count. This is intended to
2134 * be paired with a follow on vdropl() to release the remaining hold count.
2135 * In this way we may vgone() a vnode with a 0 usecount without risk of
2136 * having it end up on a free list because the hold count is kept above 0.
2137 */
2138 static void
2139 v_decr_useonly(struct vnode *vp)
2140 {
2141
2142 ASSERT_VI_LOCKED(vp, __FUNCTION__);
2143 VNASSERT(vp->v_usecount > 0, vp,
2144 ("v_decr_useonly: negative usecount"));
2145 CTR2(KTR_VFS, "%s: vp %p", __func__, vp);
2146 vp->v_usecount--;
2147 if (vp->v_type == VCHR && vp->v_rdev != NULL) {
2148 dev_lock();
2149 vp->v_rdev->si_usecount--;
2150 dev_unlock();
2151 }
2152 }
2153
2154 /*
2155 * Grab a particular vnode from the free list, increment its
2156 * reference count and lock it. VI_DOOMED is set if the vnode
2157 * is being destroyed. Only callers who specify LK_RETRY will
2158 * see doomed vnodes. If inactive processing was delayed in
2159 * vput try to do it here.
2160 */
2161 int
2162 vget(struct vnode *vp, int flags, struct thread *td)
2163 {
2164 int error;
2165
2166 error = 0;
2167 VNASSERT((flags & LK_TYPE_MASK) != 0, vp,
2168 ("vget: invalid lock operation"));
2169 CTR3(KTR_VFS, "%s: vp %p with flags %d", __func__, vp, flags);
2170
2171 if ((flags & LK_INTERLOCK) == 0)
2172 VI_LOCK(vp);
2173 vholdl(vp);
2174 if ((error = vn_lock(vp, flags | LK_INTERLOCK)) != 0) {
2175 vdrop(vp);
2176 CTR2(KTR_VFS, "%s: impossible to lock vnode %p", __func__,
2177 vp);
2178 return (error);
2179 }
2180 if (vp->v_iflag & VI_DOOMED && (flags & LK_RETRY) == 0)
2181 panic("vget: vn_lock failed to return ENOENT\n");
2182 VI_LOCK(vp);
2183 /* Upgrade our holdcnt to a usecount. */
2184 v_upgrade_usecount(vp);
2185 /*
2186 * We don't guarantee that any particular close will
2187 * trigger inactive processing so just make a best effort
2188 * here at preventing a reference to a removed file. If
2189 * we don't succeed no harm is done.
2190 */
2191 if (vp->v_iflag & VI_OWEINACT) {
2192 if (VOP_ISLOCKED(vp) == LK_EXCLUSIVE &&
2193 (flags & LK_NOWAIT) == 0)
2194 vinactive(vp, td);
2195 vp->v_iflag &= ~VI_OWEINACT;
2196 }
2197 VI_UNLOCK(vp);
2198 return (0);
2199 }
2200
2201 /*
2202 * Increase the reference count of a vnode.
2203 */
2204 void
2205 vref(struct vnode *vp)
2206 {
2207
2208 CTR2(KTR_VFS, "%s: vp %p", __func__, vp);
2209 VI_LOCK(vp);
2210 v_incr_usecount(vp);
2211 VI_UNLOCK(vp);
2212 }
2213
2214 /*
2215 * Return reference count of a vnode.
2216 *
2217 * The results of this call are only guaranteed when some mechanism other
2218 * than the VI lock is used to stop other processes from gaining references
2219 * to the vnode. This may be the case if the caller holds the only reference.
2220 * This is also useful when stale data is acceptable as race conditions may
2221 * be accounted for by some other means.
2222 */
2223 int
2224 vrefcnt(struct vnode *vp)
2225 {
2226 int usecnt;
2227
2228 VI_LOCK(vp);
2229 usecnt = vp->v_usecount;
2230 VI_UNLOCK(vp);
2231
2232 return (usecnt);
2233 }
2234
2235 #define VPUTX_VRELE 1
2236 #define VPUTX_VPUT 2
2237 #define VPUTX_VUNREF 3
2238
2239 static void
2240 vputx(struct vnode *vp, int func)
2241 {
2242 int error;
2243
2244 KASSERT(vp != NULL, ("vputx: null vp"));
2245 if (func == VPUTX_VUNREF)
2246 ASSERT_VOP_LOCKED(vp, "vunref");
2247 else if (func == VPUTX_VPUT)
2248 ASSERT_VOP_LOCKED(vp, "vput");
2249 else
2250 KASSERT(func == VPUTX_VRELE, ("vputx: wrong func"));
2251 CTR2(KTR_VFS, "%s: vp %p", __func__, vp);
2252 VI_LOCK(vp);
2253
2254 /* Skip this v_writecount check if we're going to panic below. */
2255 VNASSERT(vp->v_writecount < vp->v_usecount || vp->v_usecount < 1, vp,
2256 ("vputx: missed vn_close"));
2257 error = 0;
2258
2259 if (vp->v_usecount > 1 || ((vp->v_iflag & VI_DOINGINACT) &&
2260 vp->v_usecount == 1)) {
2261 if (func == VPUTX_VPUT)
2262 VOP_UNLOCK(vp, 0);
2263 v_decr_usecount(vp);
2264 return;
2265 }
2266
2267 if (vp->v_usecount != 1) {
2268 vprint("vputx: negative ref count", vp);
2269 panic("vputx: negative ref cnt");
2270 }
2271 CTR2(KTR_VFS, "%s: return vnode %p to the freelist", __func__, vp);
2272 /*
2273 * We want to hold the vnode until the inactive finishes to
2274 * prevent vgone() races. We drop the use count here and the
2275 * hold count below when we're done.
2276 */
2277 v_decr_useonly(vp);
2278 /*
2279 * We must call VOP_INACTIVE with the node locked. Mark
2280 * as VI_DOINGINACT to avoid recursion.
2281 */
2282 vp->v_iflag |= VI_OWEINACT;
2283 switch (func) {
2284 case VPUTX_VRELE:
2285 error = vn_lock(vp, LK_EXCLUSIVE | LK_INTERLOCK);
2286 VI_LOCK(vp);
2287 break;
2288 case VPUTX_VPUT:
2289 if (VOP_ISLOCKED(vp) != LK_EXCLUSIVE) {
2290 error = VOP_LOCK(vp, LK_UPGRADE | LK_INTERLOCK |
2291 LK_NOWAIT);
2292 VI_LOCK(vp);
2293 }
2294 break;
2295 case VPUTX_VUNREF:
2296 if (VOP_ISLOCKED(vp) != LK_EXCLUSIVE) {
2297 error = VOP_LOCK(vp, LK_TRYUPGRADE | LK_INTERLOCK);
2298 VI_LOCK(vp);
2299 }
2300 break;
2301 }
2302 if (vp->v_usecount > 0)
2303 vp->v_iflag &= ~VI_OWEINACT;
2304 if (error == 0) {
2305 if (vp->v_iflag & VI_OWEINACT)
2306 vinactive(vp, curthread);
2307 if (func != VPUTX_VUNREF)
2308 VOP_UNLOCK(vp, 0);
2309 }
2310 vdropl(vp);
2311 }
2312
2313 /*
2314 * Vnode put/release.
2315 * If count drops to zero, call inactive routine and return to freelist.
2316 */
2317 void
2318 vrele(struct vnode *vp)
2319 {
2320
2321 vputx(vp, VPUTX_VRELE);
2322 }
2323
2324 /*
2325 * Release an already locked vnode. This give the same effects as
2326 * unlock+vrele(), but takes less time and avoids releasing and
2327 * re-aquiring the lock (as vrele() acquires the lock internally.)
2328 */
2329 void
2330 vput(struct vnode *vp)
2331 {
2332
2333 vputx(vp, VPUTX_VPUT);
2334 }
2335
2336 /*
2337 * Release an exclusively locked vnode. Do not unlock the vnode lock.
2338 */
2339 void
2340 vunref(struct vnode *vp)
2341 {
2342
2343 vputx(vp, VPUTX_VUNREF);
2344 }
2345
2346 /*
2347 * Somebody doesn't want the vnode recycled.
2348 */
2349 void
2350 vhold(struct vnode *vp)
2351 {
2352
2353 VI_LOCK(vp);
2354 vholdl(vp);
2355 VI_UNLOCK(vp);
2356 }
2357
2358 /*
2359 * Increase the hold count and activate if this is the first reference.
2360 */
2361 void
2362 vholdl(struct vnode *vp)
2363 {
2364 struct mount *mp;
2365
2366 CTR2(KTR_VFS, "%s: vp %p", __func__, vp);
2367 #ifdef INVARIANTS
2368 /* getnewvnode() calls v_incr_usecount() without holding interlock. */
2369 if (vp->v_type != VNON || vp->v_data != NULL)
2370 ASSERT_VI_LOCKED(vp, "vholdl");
2371 #endif
2372 vp->v_holdcnt++;
2373 if ((vp->v_iflag & VI_FREE) == 0)
2374 return;
2375 VNASSERT(vp->v_holdcnt == 1, vp, ("vholdl: wrong hold count"));
2376 VNASSERT(vp->v_op != NULL, vp, ("vholdl: vnode already reclaimed."));
2377 /*
2378 * Remove a vnode from the free list, mark it as in use,
2379 * and put it on the active list.
2380 */
2381 mtx_lock(&vnode_free_list_mtx);
2382 TAILQ_REMOVE(&vnode_free_list, vp, v_actfreelist);
2383 freevnodes--;
2384 vp->v_iflag &= ~(VI_FREE|VI_AGE);
2385 KASSERT((vp->v_iflag & VI_ACTIVE) == 0,
2386 ("Activating already active vnode"));
2387 vp->v_iflag |= VI_ACTIVE;
2388 mp = vp->v_mount;
2389 TAILQ_INSERT_HEAD(&mp->mnt_activevnodelist, vp, v_actfreelist);
2390 mp->mnt_activevnodelistsize++;
2391 mtx_unlock(&vnode_free_list_mtx);
2392 }
2393
2394 /*
2395 * Note that there is one less who cares about this vnode.
2396 * vdrop() is the opposite of vhold().
2397 */
2398 void
2399 vdrop(struct vnode *vp)
2400 {
2401
2402 VI_LOCK(vp);
2403 vdropl(vp);
2404 }
2405
2406 /*
2407 * Drop the hold count of the vnode. If this is the last reference to
2408 * the vnode we place it on the free list unless it has been vgone'd
2409 * (marked VI_DOOMED) in which case we will free it.
2410 */
2411 void
2412 vdropl(struct vnode *vp)
2413 {
2414 struct bufobj *bo;
2415 struct mount *mp;
2416 int active;
2417
2418 ASSERT_VI_LOCKED(vp, "vdropl");
2419 CTR2(KTR_VFS, "%s: vp %p", __func__, vp);
2420 if (vp->v_holdcnt <= 0)
2421 panic("vdrop: holdcnt %d", vp->v_holdcnt);
2422 vp->v_holdcnt--;
2423 if (vp->v_holdcnt > 0) {
2424 VI_UNLOCK(vp);
2425 return;
2426 }
2427 if ((vp->v_iflag & VI_DOOMED) == 0) {
2428 /*
2429 * Mark a vnode as free: remove it from its active list
2430 * and put it up for recycling on the freelist.
2431 */
2432 VNASSERT(vp->v_op != NULL, vp,
2433 ("vdropl: vnode already reclaimed."));
2434 VNASSERT((vp->v_iflag & VI_FREE) == 0, vp,
2435 ("vnode already free"));
2436 VNASSERT(vp->v_holdcnt == 0, vp,
2437 ("vdropl: freeing when we shouldn't"));
2438 active = vp->v_iflag & VI_ACTIVE;
2439 if ((vp->v_iflag & VI_OWEINACT) == 0) {
2440 vp->v_iflag &= ~VI_ACTIVE;
2441 mp = vp->v_mount;
2442 mtx_lock(&vnode_free_list_mtx);
2443 if (active) {
2444 TAILQ_REMOVE(&mp->mnt_activevnodelist, vp,
2445 v_actfreelist);
2446 mp->mnt_activevnodelistsize--;
2447 }
2448 if (vp->v_iflag & VI_AGE) {
2449 TAILQ_INSERT_HEAD(&vnode_free_list, vp,
2450 v_actfreelist);
2451 } else {
2452 TAILQ_INSERT_TAIL(&vnode_free_list, vp,
2453 v_actfreelist);
2454 }
2455 freevnodes++;
2456 vp->v_iflag &= ~VI_AGE;
2457 vp->v_iflag |= VI_FREE;
2458 mtx_unlock(&vnode_free_list_mtx);
2459 } else {
2460 atomic_add_long(&free_owe_inact, 1);
2461 }
2462 VI_UNLOCK(vp);
2463 return;
2464 }
2465 /*
2466 * The vnode has been marked for destruction, so free it.
2467 */
2468 CTR2(KTR_VFS, "%s: destroying the vnode %p", __func__, vp);
2469 atomic_subtract_long(&numvnodes, 1);
2470 bo = &vp->v_bufobj;
2471 VNASSERT((vp->v_iflag & VI_FREE) == 0, vp,
2472 ("cleaned vnode still on the free list."));
2473 VNASSERT(vp->v_data == NULL, vp, ("cleaned vnode isn't"));
2474 VNASSERT(vp->v_holdcnt == 0, vp, ("Non-zero hold count"));
2475 VNASSERT(vp->v_usecount == 0, vp, ("Non-zero use count"));
2476 VNASSERT(vp->v_writecount == 0, vp, ("Non-zero write count"));
2477 VNASSERT(bo->bo_numoutput == 0, vp, ("Clean vnode has pending I/O's"));
2478 VNASSERT(bo->bo_clean.bv_cnt == 0, vp, ("cleanbufcnt not 0"));
2479 VNASSERT(pctrie_is_empty(&bo->bo_clean.bv_root), vp,
2480 ("clean blk trie not empty"));
2481 VNASSERT(bo->bo_dirty.bv_cnt == 0, vp, ("dirtybufcnt not 0"));
2482 VNASSERT(pctrie_is_empty(&bo->bo_dirty.bv_root), vp,
2483 ("dirty blk trie not empty"));
2484 VNASSERT(TAILQ_EMPTY(&vp->v_cache_dst), vp, ("vp has namecache dst"));
2485 VNASSERT(LIST_EMPTY(&vp->v_cache_src), vp, ("vp has namecache src"));
2486 VNASSERT(vp->v_cache_dd == NULL, vp, ("vp has namecache for .."));
2487 VI_UNLOCK(vp);
2488 #ifdef MAC
2489 mac_vnode_destroy(vp);
2490 #endif
2491 if (vp->v_pollinfo != NULL)
2492 destroy_vpollinfo(vp->v_pollinfo);
2493 #ifdef INVARIANTS
2494 /* XXX Elsewhere we detect an already freed vnode via NULL v_op. */
2495 vp->v_op = NULL;
2496 #endif
2497 rangelock_destroy(&vp->v_rl);
2498 lockdestroy(vp->v_vnlock);
2499 mtx_destroy(&vp->v_interlock);
2500 rw_destroy(BO_LOCKPTR(bo));
2501 uma_zfree(vnode_zone, vp);
2502 }
2503
2504 /*
2505 * Call VOP_INACTIVE on the vnode and manage the DOINGINACT and OWEINACT
2506 * flags. DOINGINACT prevents us from recursing in calls to vinactive.
2507 * OWEINACT tracks whether a vnode missed a call to inactive due to a
2508 * failed lock upgrade.
2509 */
2510 void
2511 vinactive(struct vnode *vp, struct thread *td)
2512 {
2513 struct vm_object *obj;
2514
2515 ASSERT_VOP_ELOCKED(vp, "vinactive");
2516 ASSERT_VI_LOCKED(vp, "vinactive");
2517 VNASSERT((vp->v_iflag & VI_DOINGINACT) == 0, vp,
2518 ("vinactive: recursed on VI_DOINGINACT"));
2519 CTR2(KTR_VFS, "%s: vp %p", __func__, vp);
2520 vp->v_iflag |= VI_DOINGINACT;
2521 vp->v_iflag &= ~VI_OWEINACT;
2522 VI_UNLOCK(vp);
2523 /*
2524 * Before moving off the active list, we must be sure that any
2525 * modified pages are on the vnode's dirty list since these will
2526 * no longer be checked once the vnode is on the inactive list.
2527 * Because the vnode vm object keeps a hold reference on the vnode
2528 * if there is at least one resident non-cached page, the vnode
2529 * cannot leave the active list without the page cleanup done.
2530 */
2531 obj = vp->v_object;
2532 if (obj != NULL && (obj->flags & OBJ_MIGHTBEDIRTY) != 0) {
2533 VM_OBJECT_WLOCK(obj);
2534 vm_object_page_clean(obj, 0, 0, OBJPC_NOSYNC);
2535 VM_OBJECT_WUNLOCK(obj);
2536 }
2537 VOP_INACTIVE(vp, td);
2538 VI_LOCK(vp);
2539 VNASSERT(vp->v_iflag & VI_DOINGINACT, vp,
2540 ("vinactive: lost VI_DOINGINACT"));
2541 vp->v_iflag &= ~VI_DOINGINACT;
2542 }
2543
2544 /*
2545 * Remove any vnodes in the vnode table belonging to mount point mp.
2546 *
2547 * If FORCECLOSE is not specified, there should not be any active ones,
2548 * return error if any are found (nb: this is a user error, not a
2549 * system error). If FORCECLOSE is specified, detach any active vnodes
2550 * that are found.
2551 *
2552 * If WRITECLOSE is set, only flush out regular file vnodes open for
2553 * writing.
2554 *
2555 * SKIPSYSTEM causes any vnodes marked VV_SYSTEM to be skipped.
2556 *
2557 * `rootrefs' specifies the base reference count for the root vnode
2558 * of this filesystem. The root vnode is considered busy if its
2559 * v_usecount exceeds this value. On a successful return, vflush(, td)
2560 * will call vrele() on the root vnode exactly rootrefs times.
2561 * If the SKIPSYSTEM or WRITECLOSE flags are specified, rootrefs must
2562 * be zero.
2563 */
2564 #ifdef DIAGNOSTIC
2565 static int busyprt = 0; /* print out busy vnodes */
2566 SYSCTL_INT(_debug, OID_AUTO, busyprt, CTLFLAG_RW, &busyprt, 0, "Print out busy vnodes");
2567 #endif
2568
2569 int
2570 vflush(struct mount *mp, int rootrefs, int flags, struct thread *td)
2571 {
2572 struct vnode *vp, *mvp, *rootvp = NULL;
2573 struct vattr vattr;
2574 int busy = 0, error;
2575
2576 CTR4(KTR_VFS, "%s: mp %p with rootrefs %d and flags %d", __func__, mp,
2577 rootrefs, flags);
2578 if (rootrefs > 0) {
2579 KASSERT((flags & (SKIPSYSTEM | WRITECLOSE)) == 0,
2580 ("vflush: bad args"));
2581 /*
2582 * Get the filesystem root vnode. We can vput() it
2583 * immediately, since with rootrefs > 0, it won't go away.
2584 */
2585 if ((error = VFS_ROOT(mp, LK_EXCLUSIVE, &rootvp)) != 0) {
2586 CTR2(KTR_VFS, "%s: vfs_root lookup failed with %d",
2587 __func__, error);
2588 return (error);
2589 }
2590 vput(rootvp);
2591 }
2592 loop:
2593 MNT_VNODE_FOREACH_ALL(vp, mp, mvp) {
2594 vholdl(vp);
2595 error = vn_lock(vp, LK_INTERLOCK | LK_EXCLUSIVE);
2596 if (error) {
2597 vdrop(vp);
2598 MNT_VNODE_FOREACH_ALL_ABORT(mp, mvp);
2599 goto loop;
2600 }
2601 /*
2602 * Skip over a vnodes marked VV_SYSTEM.
2603 */
2604 if ((flags & SKIPSYSTEM) && (vp->v_vflag & VV_SYSTEM)) {
2605 VOP_UNLOCK(vp, 0);
2606 vdrop(vp);
2607 continue;
2608 }
2609 /*
2610 * If WRITECLOSE is set, flush out unlinked but still open
2611 * files (even if open only for reading) and regular file
2612 * vnodes open for writing.
2613 */
2614 if (flags & WRITECLOSE) {
2615 if (vp->v_object != NULL) {
2616 VM_OBJECT_WLOCK(vp->v_object);
2617 vm_object_page_clean(vp->v_object, 0, 0, 0);
2618 VM_OBJECT_WUNLOCK(vp->v_object);
2619 }
2620 error = VOP_FSYNC(vp, MNT_WAIT, td);
2621 if (error != 0) {
2622 VOP_UNLOCK(vp, 0);
2623 vdrop(vp);
2624 MNT_VNODE_FOREACH_ALL_ABORT(mp, mvp);
2625 return (error);
2626 }
2627 error = VOP_GETATTR(vp, &vattr, td->td_ucred);
2628 VI_LOCK(vp);
2629
2630 if ((vp->v_type == VNON ||
2631 (error == 0 && vattr.va_nlink > 0)) &&
2632 (vp->v_writecount == 0 || vp->v_type != VREG)) {
2633 VOP_UNLOCK(vp, 0);
2634 vdropl(vp);
2635 continue;
2636 }
2637 } else
2638 VI_LOCK(vp);
2639 /*
2640 * With v_usecount == 0, all we need to do is clear out the
2641 * vnode data structures and we are done.
2642 *
2643 * If FORCECLOSE is set, forcibly close the vnode.
2644 */
2645 if (vp->v_usecount == 0 || (flags & FORCECLOSE)) {
2646 VNASSERT(vp->v_usecount == 0 ||
2647 vp->v_op != &devfs_specops ||
2648 (vp->v_type != VCHR && vp->v_type != VBLK), vp,
2649 ("device VNODE %p is FORCECLOSED", vp));
2650 vgonel(vp);
2651 } else {
2652 busy++;
2653 #ifdef DIAGNOSTIC
2654 if (busyprt)
2655 vprint("vflush: busy vnode", vp);
2656 #endif
2657 }
2658 VOP_UNLOCK(vp, 0);
2659 vdropl(vp);
2660 }
2661 if (rootrefs > 0 && (flags & FORCECLOSE) == 0) {
2662 /*
2663 * If just the root vnode is busy, and if its refcount
2664 * is equal to `rootrefs', then go ahead and kill it.
2665 */
2666 VI_LOCK(rootvp);
2667 KASSERT(busy > 0, ("vflush: not busy"));
2668 VNASSERT(rootvp->v_usecount >= rootrefs, rootvp,
2669 ("vflush: usecount %d < rootrefs %d",
2670 rootvp->v_usecount, rootrefs));
2671 if (busy == 1 && rootvp->v_usecount == rootrefs) {
2672 VOP_LOCK(rootvp, LK_EXCLUSIVE|LK_INTERLOCK);
2673 vgone(rootvp);
2674 VOP_UNLOCK(rootvp, 0);
2675 busy = 0;
2676 } else
2677 VI_UNLOCK(rootvp);
2678 }
2679 if (busy) {
2680 CTR2(KTR_VFS, "%s: failing as %d vnodes are busy", __func__,
2681 busy);
2682 return (EBUSY);
2683 }
2684 for (; rootrefs > 0; rootrefs--)
2685 vrele(rootvp);
2686 return (0);
2687 }
2688
2689 /*
2690 * Recycle an unused vnode to the front of the free list.
2691 */
2692 int
2693 vrecycle(struct vnode *vp)
2694 {
2695 int recycled;
2696
2697 ASSERT_VOP_ELOCKED(vp, "vrecycle");
2698 CTR2(KTR_VFS, "%s: vp %p", __func__, vp);
2699 recycled = 0;
2700 VI_LOCK(vp);
2701 if (vp->v_usecount == 0) {
2702 recycled = 1;
2703 vgonel(vp);
2704 }
2705 VI_UNLOCK(vp);
2706 return (recycled);
2707 }
2708
2709 /*
2710 * Eliminate all activity associated with a vnode
2711 * in preparation for reuse.
2712 */
2713 void
2714 vgone(struct vnode *vp)
2715 {
2716 VI_LOCK(vp);
2717 vgonel(vp);
2718 VI_UNLOCK(vp);
2719 }
2720
2721 static void
2722 notify_lowervp_vfs_dummy(struct mount *mp __unused,
2723 struct vnode *lowervp __unused)
2724 {
2725 }
2726
2727 /*
2728 * Notify upper mounts about reclaimed or unlinked vnode.
2729 */
2730 void
2731 vfs_notify_upper(struct vnode *vp, int event)
2732 {
2733 static struct vfsops vgonel_vfsops = {
2734 .vfs_reclaim_lowervp = notify_lowervp_vfs_dummy,
2735 .vfs_unlink_lowervp = notify_lowervp_vfs_dummy,
2736 };
2737 struct mount *mp, *ump, *mmp;
2738
2739 mp = vp->v_mount;
2740 if (mp == NULL)
2741 return;
2742
2743 MNT_ILOCK(mp);
2744 if (TAILQ_EMPTY(&mp->mnt_uppers))
2745 goto unlock;
2746 MNT_IUNLOCK(mp);
2747 mmp = malloc(sizeof(struct mount), M_TEMP, M_WAITOK | M_ZERO);
2748 mmp->mnt_op = &vgonel_vfsops;
2749 mmp->mnt_kern_flag |= MNTK_MARKER;
2750 MNT_ILOCK(mp);
2751 mp->mnt_kern_flag |= MNTK_VGONE_UPPER;
2752 for (ump = TAILQ_FIRST(&mp->mnt_uppers); ump != NULL;) {
2753 if ((ump->mnt_kern_flag & MNTK_MARKER) != 0) {
2754 ump = TAILQ_NEXT(ump, mnt_upper_link);
2755 continue;
2756 }
2757 TAILQ_INSERT_AFTER(&mp->mnt_uppers, ump, mmp, mnt_upper_link);
2758 MNT_IUNLOCK(mp);
2759 switch (event) {
2760 case VFS_NOTIFY_UPPER_RECLAIM:
2761 VFS_RECLAIM_LOWERVP(ump, vp);
2762 break;
2763 case VFS_NOTIFY_UPPER_UNLINK:
2764 VFS_UNLINK_LOWERVP(ump, vp);
2765 break;
2766 default:
2767 KASSERT(0, ("invalid event %d", event));
2768 break;
2769 }
2770 MNT_ILOCK(mp);
2771 ump = TAILQ_NEXT(mmp, mnt_upper_link);
2772 TAILQ_REMOVE(&mp->mnt_uppers, mmp, mnt_upper_link);
2773 }
2774 free(mmp, M_TEMP);
2775 mp->mnt_kern_flag &= ~MNTK_VGONE_UPPER;
2776 if ((mp->mnt_kern_flag & MNTK_VGONE_WAITER) != 0) {
2777 mp->mnt_kern_flag &= ~MNTK_VGONE_WAITER;
2778 wakeup(&mp->mnt_uppers);
2779 }
2780 unlock:
2781 MNT_IUNLOCK(mp);
2782 }
2783
2784 /*
2785 * vgone, with the vp interlock held.
2786 */
2787 void
2788 vgonel(struct vnode *vp)
2789 {
2790 struct thread *td;
2791 int oweinact;
2792 int active;
2793 struct mount *mp;
2794
2795 ASSERT_VOP_ELOCKED(vp, "vgonel");
2796 ASSERT_VI_LOCKED(vp, "vgonel");
2797 VNASSERT(vp->v_holdcnt, vp,
2798 ("vgonel: vp %p has no reference.", vp));
2799 CTR2(KTR_VFS, "%s: vp %p", __func__, vp);
2800 td = curthread;
2801
2802 /*
2803 * Don't vgonel if we're already doomed.
2804 */
2805 if (vp->v_iflag & VI_DOOMED)
2806 return;
2807 vp->v_iflag |= VI_DOOMED;
2808
2809 /*
2810 * Check to see if the vnode is in use. If so, we have to call
2811 * VOP_CLOSE() and VOP_INACTIVE().
2812 */
2813 active = vp->v_usecount;
2814 oweinact = (vp->v_iflag & VI_OWEINACT);
2815 VI_UNLOCK(vp);
2816 vfs_notify_upper(vp, VFS_NOTIFY_UPPER_RECLAIM);
2817
2818 /*
2819 * If purging an active vnode, it must be closed and
2820 * deactivated before being reclaimed.
2821 */
2822 if (active)
2823 VOP_CLOSE(vp, FNONBLOCK, NOCRED, td);
2824 if (oweinact || active) {
2825 VI_LOCK(vp);
2826 if ((vp->v_iflag & VI_DOINGINACT) == 0)
2827 vinactive(vp, td);
2828 VI_UNLOCK(vp);
2829 }
2830 if (vp->v_type == VSOCK)
2831 vfs_unp_reclaim(vp);
2832
2833 /*
2834 * Clean out any buffers associated with the vnode.
2835 * If the flush fails, just toss the buffers.
2836 */
2837 mp = NULL;
2838 if (!TAILQ_EMPTY(&vp->v_bufobj.bo_dirty.bv_hd))
2839 (void) vn_start_secondary_write(vp, &mp, V_WAIT);
2840 if (vinvalbuf(vp, V_SAVE, 0, 0) != 0) {
2841 while (vinvalbuf(vp, 0, 0, 0) != 0)
2842 ;
2843 }
2844 #ifdef INVARIANTS
2845 BO_LOCK(&vp->v_bufobj);
2846 KASSERT(TAILQ_EMPTY(&vp->v_bufobj.bo_dirty.bv_hd) &&
2847 vp->v_bufobj.bo_dirty.bv_cnt == 0 &&
2848 TAILQ_EMPTY(&vp->v_bufobj.bo_clean.bv_hd) &&
2849 vp->v_bufobj.bo_clean.bv_cnt == 0,
2850 ("vp %p bufobj not invalidated", vp));
2851 vp->v_bufobj.bo_flag |= BO_DEAD;
2852 BO_UNLOCK(&vp->v_bufobj);
2853 #endif
2854
2855 /*
2856 * Reclaim the vnode.
2857 */
2858 if (VOP_RECLAIM(vp, td))
2859 panic("vgone: cannot reclaim");
2860 if (mp != NULL)
2861 vn_finished_secondary_write(mp);
2862 VNASSERT(vp->v_object == NULL, vp,
2863 ("vop_reclaim left v_object vp=%p, tag=%s", vp, vp->v_tag));
2864 /*
2865 * Clear the advisory locks and wake up waiting threads.
2866 */
2867 (void)VOP_ADVLOCKPURGE(vp);
2868 /*
2869 * Delete from old mount point vnode list.
2870 */
2871 delmntque(vp);
2872 cache_purge(vp);
2873 /*
2874 * Done with purge, reset to the standard lock and invalidate
2875 * the vnode.
2876 */
2877 VI_LOCK(vp);
2878 vp->v_vnlock = &vp->v_lock;
2879 vp->v_op = &dead_vnodeops;
2880 vp->v_tag = "none";
2881 vp->v_type = VBAD;
2882 }
2883
2884 /*
2885 * Calculate the total number of references to a special device.
2886 */
2887 int
2888 vcount(struct vnode *vp)
2889 {
2890 int count;
2891
2892 dev_lock();
2893 count = vp->v_rdev->si_usecount;
2894 dev_unlock();
2895 return (count);
2896 }
2897
2898 /*
2899 * Same as above, but using the struct cdev *as argument
2900 */
2901 int
2902 count_dev(struct cdev *dev)
2903 {
2904 int count;
2905
2906 dev_lock();
2907 count = dev->si_usecount;
2908 dev_unlock();
2909 return(count);
2910 }
2911
2912 /*
2913 * Print out a description of a vnode.
2914 */
2915 static char *typename[] =
2916 {"VNON", "VREG", "VDIR", "VBLK", "VCHR", "VLNK", "VSOCK", "VFIFO", "VBAD",
2917 "VMARKER"};
2918
2919 void
2920 vn_printf(struct vnode *vp, const char *fmt, ...)
2921 {
2922 va_list ap;
2923 char buf[256], buf2[16];
2924 u_long flags;
2925
2926 va_start(ap, fmt);
2927 vprintf(fmt, ap);
2928 va_end(ap);
2929 printf("%p: ", (void *)vp);
2930 printf("tag %s, type %s\n", vp->v_tag, typename[vp->v_type]);
2931 printf(" usecount %d, writecount %d, refcount %d mountedhere %p\n",
2932 vp->v_usecount, vp->v_writecount, vp->v_holdcnt, vp->v_mountedhere);
2933 buf[0] = '\0';
2934 buf[1] = '\0';
2935 if (vp->v_vflag & VV_ROOT)
2936 strlcat(buf, "|VV_ROOT", sizeof(buf));
2937 if (vp->v_vflag & VV_ISTTY)
2938 strlcat(buf, "|VV_ISTTY", sizeof(buf));
2939 if (vp->v_vflag & VV_NOSYNC)
2940 strlcat(buf, "|VV_NOSYNC", sizeof(buf));
2941 if (vp->v_vflag & VV_ETERNALDEV)
2942 strlcat(buf, "|VV_ETERNALDEV", sizeof(buf));
2943 if (vp->v_vflag & VV_CACHEDLABEL)
2944 strlcat(buf, "|VV_CACHEDLABEL", sizeof(buf));
2945 if (vp->v_vflag & VV_TEXT)
2946 strlcat(buf, "|VV_TEXT", sizeof(buf));
2947 if (vp->v_vflag & VV_COPYONWRITE)
2948 strlcat(buf, "|VV_COPYONWRITE", sizeof(buf));
2949 if (vp->v_vflag & VV_SYSTEM)
2950 strlcat(buf, "|VV_SYSTEM", sizeof(buf));
2951 if (vp->v_vflag & VV_PROCDEP)
2952 strlcat(buf, "|VV_PROCDEP", sizeof(buf));
2953 if (vp->v_vflag & VV_NOKNOTE)
2954 strlcat(buf, "|VV_NOKNOTE", sizeof(buf));
2955 if (vp->v_vflag & VV_DELETED)
2956 strlcat(buf, "|VV_DELETED", sizeof(buf));
2957 if (vp->v_vflag & VV_MD)
2958 strlcat(buf, "|VV_MD", sizeof(buf));
2959 if (vp->v_vflag & VV_FORCEINSMQ)
2960 strlcat(buf, "|VV_FORCEINSMQ", sizeof(buf));
2961 flags = vp->v_vflag & ~(VV_ROOT | VV_ISTTY | VV_NOSYNC | VV_ETERNALDEV |
2962 VV_CACHEDLABEL | VV_TEXT | VV_COPYONWRITE | VV_SYSTEM | VV_PROCDEP |
2963 VV_NOKNOTE | VV_DELETED | VV_MD | VV_FORCEINSMQ);
2964 if (flags != 0) {
2965 snprintf(buf2, sizeof(buf2), "|VV(0x%lx)", flags);
2966 strlcat(buf, buf2, sizeof(buf));
2967 }
2968 if (vp->v_iflag & VI_MOUNT)
2969 strlcat(buf, "|VI_MOUNT", sizeof(buf));
2970 if (vp->v_iflag & VI_AGE)
2971 strlcat(buf, "|VI_AGE", sizeof(buf));
2972 if (vp->v_iflag & VI_DOOMED)
2973 strlcat(buf, "|VI_DOOMED", sizeof(buf));
2974 if (vp->v_iflag & VI_FREE)
2975 strlcat(buf, "|VI_FREE", sizeof(buf));
2976 if (vp->v_iflag & VI_ACTIVE)
2977 strlcat(buf, "|VI_ACTIVE", sizeof(buf));
2978 if (vp->v_iflag & VI_DOINGINACT)
2979 strlcat(buf, "|VI_DOINGINACT", sizeof(buf));
2980 if (vp->v_iflag & VI_OWEINACT)
2981 strlcat(buf, "|VI_OWEINACT", sizeof(buf));
2982 flags = vp->v_iflag & ~(VI_MOUNT | VI_AGE | VI_DOOMED | VI_FREE |
2983 VI_ACTIVE | VI_DOINGINACT | VI_OWEINACT);
2984 if (flags != 0) {
2985 snprintf(buf2, sizeof(buf2), "|VI(0x%lx)", flags);
2986 strlcat(buf, buf2, sizeof(buf));
2987 }
2988 printf(" flags (%s)\n", buf + 1);
2989 if (mtx_owned(VI_MTX(vp)))
2990 printf(" VI_LOCKed");
2991 if (vp->v_object != NULL)
2992 printf(" v_object %p ref %d pages %d "
2993 "cleanbuf %d dirtybuf %d\n",
2994 vp->v_object, vp->v_object->ref_count,
2995 vp->v_object->resident_page_count,
2996 vp->v_bufobj.bo_dirty.bv_cnt,
2997 vp->v_bufobj.bo_clean.bv_cnt);
2998 printf(" ");
2999 lockmgr_printinfo(vp->v_vnlock);
3000 if (vp->v_data != NULL)
3001 VOP_PRINT(vp);
3002 }
3003
3004 #ifdef DDB
3005 /*
3006 * List all of the locked vnodes in the system.
3007 * Called when debugging the kernel.
3008 */
3009 DB_SHOW_COMMAND(lockedvnods, lockedvnodes)
3010 {
3011 struct mount *mp;
3012 struct vnode *vp;
3013
3014 /*
3015 * Note: because this is DDB, we can't obey the locking semantics
3016 * for these structures, which means we could catch an inconsistent
3017 * state and dereference a nasty pointer. Not much to be done
3018 * about that.
3019 */
3020 db_printf("Locked vnodes\n");
3021 TAILQ_FOREACH(mp, &mountlist, mnt_list) {
3022 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) {
3023 if (vp->v_type != VMARKER && VOP_ISLOCKED(vp))
3024 vprint("", vp);
3025 }
3026 }
3027 }
3028
3029 /*
3030 * Show details about the given vnode.
3031 */
3032 DB_SHOW_COMMAND(vnode, db_show_vnode)
3033 {
3034 struct vnode *vp;
3035
3036 if (!have_addr)
3037 return;
3038 vp = (struct vnode *)addr;
3039 vn_printf(vp, "vnode ");
3040 }
3041
3042 /*
3043 * Show details about the given mount point.
3044 */
3045 DB_SHOW_COMMAND(mount, db_show_mount)
3046 {
3047 struct mount *mp;
3048 struct vfsopt *opt;
3049 struct statfs *sp;
3050 struct vnode *vp;
3051 char buf[512];
3052 uint64_t mflags;
3053 u_int flags;
3054
3055 if (!have_addr) {
3056 /* No address given, print short info about all mount points. */
3057 TAILQ_FOREACH(mp, &mountlist, mnt_list) {
3058 db_printf("%p %s on %s (%s)\n", mp,
3059 mp->mnt_stat.f_mntfromname,
3060 mp->mnt_stat.f_mntonname,
3061 mp->mnt_stat.f_fstypename);
3062 if (db_pager_quit)
3063 break;
3064 }
3065 db_printf("\nMore info: show mount <addr>\n");
3066 return;
3067 }
3068
3069 mp = (struct mount *)addr;
3070 db_printf("%p %s on %s (%s)\n", mp, mp->mnt_stat.f_mntfromname,
3071 mp->mnt_stat.f_mntonname, mp->mnt_stat.f_fstypename);
3072
3073 buf[0] = '\0';
3074 mflags = mp->mnt_flag;
3075 #define MNT_FLAG(flag) do { \
3076 if (mflags & (flag)) { \
3077 if (buf[0] != '\0') \
3078 strlcat(buf, ", ", sizeof(buf)); \
3079 strlcat(buf, (#flag) + 4, sizeof(buf)); \
3080 mflags &= ~(flag); \
3081 } \
3082 } while (0)
3083 MNT_FLAG(MNT_RDONLY);
3084 MNT_FLAG(MNT_SYNCHRONOUS);
3085 MNT_FLAG(MNT_NOEXEC);
3086 MNT_FLAG(MNT_NOSUID);
3087 MNT_FLAG(MNT_NFS4ACLS);
3088 MNT_FLAG(MNT_UNION);
3089 MNT_FLAG(MNT_ASYNC);
3090 MNT_FLAG(MNT_SUIDDIR);
3091 MNT_FLAG(MNT_SOFTDEP);
3092 MNT_FLAG(MNT_NOSYMFOLLOW);
3093 MNT_FLAG(MNT_GJOURNAL);
3094 MNT_FLAG(MNT_MULTILABEL);
3095 MNT_FLAG(MNT_ACLS);
3096 MNT_FLAG(MNT_NOATIME);
3097 MNT_FLAG(MNT_NOCLUSTERR);
3098 MNT_FLAG(MNT_NOCLUSTERW);
3099 MNT_FLAG(MNT_SUJ);
3100 MNT_FLAG(MNT_EXRDONLY);
3101 MNT_FLAG(MNT_EXPORTED);
3102 MNT_FLAG(MNT_DEFEXPORTED);
3103 MNT_FLAG(MNT_EXPORTANON);
3104 MNT_FLAG(MNT_EXKERB);
3105 MNT_FLAG(MNT_EXPUBLIC);
3106 MNT_FLAG(MNT_LOCAL);
3107 MNT_FLAG(MNT_QUOTA);
3108 MNT_FLAG(MNT_ROOTFS);
3109 MNT_FLAG(MNT_USER);
3110 MNT_FLAG(MNT_IGNORE);
3111 MNT_FLAG(MNT_UPDATE);
3112 MNT_FLAG(MNT_DELEXPORT);
3113 MNT_FLAG(MNT_RELOAD);
3114 MNT_FLAG(MNT_FORCE);
3115 MNT_FLAG(MNT_SNAPSHOT);
3116 MNT_FLAG(MNT_BYFSID);
3117 #undef MNT_FLAG
3118 if (mflags != 0) {
3119 if (buf[0] != '\0')
3120 strlcat(buf, ", ", sizeof(buf));
3121 snprintf(buf + strlen(buf), sizeof(buf) - strlen(buf),
3122 "0x%016jx", mflags);
3123 }
3124 db_printf(" mnt_flag = %s\n", buf);
3125
3126 buf[0] = '\0';
3127 flags = mp->mnt_kern_flag;
3128 #define MNT_KERN_FLAG(flag) do { \
3129 if (flags & (flag)) { \
3130 if (buf[0] != '\0') \
3131 strlcat(buf, ", ", sizeof(buf)); \
3132 strlcat(buf, (#flag) + 5, sizeof(buf)); \
3133 flags &= ~(flag); \
3134 } \
3135 } while (0)
3136 MNT_KERN_FLAG(MNTK_UNMOUNTF);
3137 MNT_KERN_FLAG(MNTK_ASYNC);
3138 MNT_KERN_FLAG(MNTK_SOFTDEP);
3139 MNT_KERN_FLAG(MNTK_NOINSMNTQ);
3140 MNT_KERN_FLAG(MNTK_DRAINING);
3141 MNT_KERN_FLAG(MNTK_REFEXPIRE);
3142 MNT_KERN_FLAG(MNTK_EXTENDED_SHARED);
3143 MNT_KERN_FLAG(MNTK_SHARED_WRITES);
3144 MNT_KERN_FLAG(MNTK_NO_IOPF);
3145 MNT_KERN_FLAG(MNTK_VGONE_UPPER);
3146 MNT_KERN_FLAG(MNTK_VGONE_WAITER);
3147 MNT_KERN_FLAG(MNTK_LOOKUP_EXCL_DOTDOT);
3148 MNT_KERN_FLAG(MNTK_MARKER);
3149 MNT_KERN_FLAG(MNTK_USES_BCACHE);
3150 MNT_KERN_FLAG(MNTK_NOASYNC);
3151 MNT_KERN_FLAG(MNTK_UNMOUNT);
3152 MNT_KERN_FLAG(MNTK_MWAIT);
3153 MNT_KERN_FLAG(MNTK_SUSPEND);
3154 MNT_KERN_FLAG(MNTK_SUSPEND2);
3155 MNT_KERN_FLAG(MNTK_SUSPENDED);
3156 MNT_KERN_FLAG(MNTK_LOOKUP_SHARED);
3157 MNT_KERN_FLAG(MNTK_NOKNOTE);
3158 #undef MNT_KERN_FLAG
3159 if (flags != 0) {
3160 if (buf[0] != '\0')
3161 strlcat(buf, ", ", sizeof(buf));
3162 snprintf(buf + strlen(buf), sizeof(buf) - strlen(buf),
3163 "0x%08x", flags);
3164 }
3165 db_printf(" mnt_kern_flag = %s\n", buf);
3166
3167 db_printf(" mnt_opt = ");
3168 opt = TAILQ_FIRST(mp->mnt_opt);
3169 if (opt != NULL) {
3170 db_printf("%s", opt->name);
3171 opt = TAILQ_NEXT(opt, link);
3172 while (opt != NULL) {
3173 db_printf(", %s", opt->name);
3174 opt = TAILQ_NEXT(opt, link);
3175 }
3176 }
3177 db_printf("\n");
3178
3179 sp = &mp->mnt_stat;
3180 db_printf(" mnt_stat = { version=%u type=%u flags=0x%016jx "
3181 "bsize=%ju iosize=%ju blocks=%ju bfree=%ju bavail=%jd files=%ju "
3182 "ffree=%jd syncwrites=%ju asyncwrites=%ju syncreads=%ju "
3183 "asyncreads=%ju namemax=%u owner=%u fsid=[%d, %d] }\n",
3184 (u_int)sp->f_version, (u_int)sp->f_type, (uintmax_t)sp->f_flags,
3185 (uintmax_t)sp->f_bsize, (uintmax_t)sp->f_iosize,
3186 (uintmax_t)sp->f_blocks, (uintmax_t)sp->f_bfree,
3187 (intmax_t)sp->f_bavail, (uintmax_t)sp->f_files,
3188 (intmax_t)sp->f_ffree, (uintmax_t)sp->f_syncwrites,
3189 (uintmax_t)sp->f_asyncwrites, (uintmax_t)sp->f_syncreads,
3190 (uintmax_t)sp->f_asyncreads, (u_int)sp->f_namemax,
3191 (u_int)sp->f_owner, (int)sp->f_fsid.val[0], (int)sp->f_fsid.val[1]);
3192
3193 db_printf(" mnt_cred = { uid=%u ruid=%u",
3194 (u_int)mp->mnt_cred->cr_uid, (u_int)mp->mnt_cred->cr_ruid);
3195 if (jailed(mp->mnt_cred))
3196 db_printf(", jail=%d", mp->mnt_cred->cr_prison->pr_id);
3197 db_printf(" }\n");
3198 db_printf(" mnt_ref = %d\n", mp->mnt_ref);
3199 db_printf(" mnt_gen = %d\n", mp->mnt_gen);
3200 db_printf(" mnt_nvnodelistsize = %d\n", mp->mnt_nvnodelistsize);
3201 db_printf(" mnt_activevnodelistsize = %d\n",
3202 mp->mnt_activevnodelistsize);
3203 db_printf(" mnt_writeopcount = %d\n", mp->mnt_writeopcount);
3204 db_printf(" mnt_maxsymlinklen = %d\n", mp->mnt_maxsymlinklen);
3205 db_printf(" mnt_iosize_max = %d\n", mp->mnt_iosize_max);
3206 db_printf(" mnt_hashseed = %u\n", mp->mnt_hashseed);
3207 db_printf(" mnt_lockref = %d\n", mp->mnt_lockref);
3208 db_printf(" mnt_secondary_writes = %d\n", mp->mnt_secondary_writes);
3209 db_printf(" mnt_secondary_accwrites = %d\n",
3210 mp->mnt_secondary_accwrites);
3211 db_printf(" mnt_gjprovider = %s\n",
3212 mp->mnt_gjprovider != NULL ? mp->mnt_gjprovider : "NULL");
3213
3214 db_printf("\n\nList of active vnodes\n");
3215 TAILQ_FOREACH(vp, &mp->mnt_activevnodelist, v_actfreelist) {
3216 if (vp->v_type != VMARKER) {
3217 vn_printf(vp, "vnode ");
3218 if (db_pager_quit)
3219 break;
3220 }
3221 }
3222 db_printf("\n\nList of inactive vnodes\n");
3223 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) {
3224 if (vp->v_type != VMARKER && (vp->v_iflag & VI_ACTIVE) == 0) {
3225 vn_printf(vp, "vnode ");
3226 if (db_pager_quit)
3227 break;
3228 }
3229 }
3230 }
3231 #endif /* DDB */
3232
3233 /*
3234 * Fill in a struct xvfsconf based on a struct vfsconf.
3235 */
3236 static int
3237 vfsconf2x(struct sysctl_req *req, struct vfsconf *vfsp)
3238 {
3239 struct xvfsconf xvfsp;
3240
3241 bzero(&xvfsp, sizeof(xvfsp));
3242 strcpy(xvfsp.vfc_name, vfsp->vfc_name);
3243 xvfsp.vfc_typenum = vfsp->vfc_typenum;
3244 xvfsp.vfc_refcount = vfsp->vfc_refcount;
3245 xvfsp.vfc_flags = vfsp->vfc_flags;
3246 /*
3247 * These are unused in userland, we keep them
3248 * to not break binary compatibility.
3249 */
3250 xvfsp.vfc_vfsops = NULL;
3251 xvfsp.vfc_next = NULL;
3252 return (SYSCTL_OUT(req, &xvfsp, sizeof(xvfsp)));
3253 }
3254
3255 #ifdef COMPAT_FREEBSD32
3256 struct xvfsconf32 {
3257 uint32_t vfc_vfsops;
3258 char vfc_name[MFSNAMELEN];
3259 int32_t vfc_typenum;
3260 int32_t vfc_refcount;
3261 int32_t vfc_flags;
3262 uint32_t vfc_next;
3263 };
3264
3265 static int
3266 vfsconf2x32(struct sysctl_req *req, struct vfsconf *vfsp)
3267 {
3268 struct xvfsconf32 xvfsp;
3269
3270 strcpy(xvfsp.vfc_name, vfsp->vfc_name);
3271 xvfsp.vfc_typenum = vfsp->vfc_typenum;
3272 xvfsp.vfc_refcount = vfsp->vfc_refcount;
3273 xvfsp.vfc_flags = vfsp->vfc_flags;
3274 xvfsp.vfc_vfsops = 0;
3275 xvfsp.vfc_next = 0;
3276 return (SYSCTL_OUT(req, &xvfsp, sizeof(xvfsp)));
3277 }
3278 #endif
3279
3280 /*
3281 * Top level filesystem related information gathering.
3282 */
3283 static int
3284 sysctl_vfs_conflist(SYSCTL_HANDLER_ARGS)
3285 {
3286 struct vfsconf *vfsp;
3287 int error;
3288
3289 error = 0;
3290 vfsconf_slock();
3291 TAILQ_FOREACH(vfsp, &vfsconf, vfc_list) {
3292 #ifdef COMPAT_FREEBSD32
3293 if (req->flags & SCTL_MASK32)
3294 error = vfsconf2x32(req, vfsp);
3295 else
3296 #endif
3297 error = vfsconf2x(req, vfsp);
3298 if (error)
3299 break;
3300 }
3301 vfsconf_sunlock();
3302 return (error);
3303 }
3304
3305 SYSCTL_PROC(_vfs, OID_AUTO, conflist, CTLTYPE_OPAQUE | CTLFLAG_RD |
3306 CTLFLAG_MPSAFE, NULL, 0, sysctl_vfs_conflist,
3307 "S,xvfsconf", "List of all configured filesystems");
3308
3309 #ifndef BURN_BRIDGES
3310 static int sysctl_ovfs_conf(SYSCTL_HANDLER_ARGS);
3311
3312 static int
3313 vfs_sysctl(SYSCTL_HANDLER_ARGS)
3314 {
3315 int *name = (int *)arg1 - 1; /* XXX */
3316 u_int namelen = arg2 + 1; /* XXX */
3317 struct vfsconf *vfsp;
3318
3319 log(LOG_WARNING, "userland calling deprecated sysctl, "
3320 "please rebuild world\n");
3321
3322 #if 1 || defined(COMPAT_PRELITE2)
3323 /* Resolve ambiguity between VFS_VFSCONF and VFS_GENERIC. */
3324 if (namelen == 1)
3325 return (sysctl_ovfs_conf(oidp, arg1, arg2, req));
3326 #endif
3327
3328 switch (name[1]) {
3329 case VFS_MAXTYPENUM:
3330 if (namelen != 2)
3331 return (ENOTDIR);
3332 return (SYSCTL_OUT(req, &maxvfsconf, sizeof(int)));
3333 case VFS_CONF:
3334 if (namelen != 3)
3335 return (ENOTDIR); /* overloaded */
3336 vfsconf_slock();
3337 TAILQ_FOREACH(vfsp, &vfsconf, vfc_list) {
3338 if (vfsp->vfc_typenum == name[2])
3339 break;
3340 }
3341 vfsconf_sunlock();
3342 if (vfsp == NULL)
3343 return (EOPNOTSUPP);
3344 #ifdef COMPAT_FREEBSD32
3345 if (req->flags & SCTL_MASK32)
3346 return (vfsconf2x32(req, vfsp));
3347 else
3348 #endif
3349 return (vfsconf2x(req, vfsp));
3350 }
3351 return (EOPNOTSUPP);
3352 }
3353
3354 static SYSCTL_NODE(_vfs, VFS_GENERIC, generic, CTLFLAG_RD | CTLFLAG_SKIP |
3355 CTLFLAG_MPSAFE, vfs_sysctl,
3356 "Generic filesystem");
3357
3358 #if 1 || defined(COMPAT_PRELITE2)
3359
3360 static int
3361 sysctl_ovfs_conf(SYSCTL_HANDLER_ARGS)
3362 {
3363 int error;
3364 struct vfsconf *vfsp;
3365 struct ovfsconf ovfs;
3366
3367 vfsconf_slock();
3368 TAILQ_FOREACH(vfsp, &vfsconf, vfc_list) {
3369 bzero(&ovfs, sizeof(ovfs));
3370 ovfs.vfc_vfsops = vfsp->vfc_vfsops; /* XXX used as flag */
3371 strcpy(ovfs.vfc_name, vfsp->vfc_name);
3372 ovfs.vfc_index = vfsp->vfc_typenum;
3373 ovfs.vfc_refcount = vfsp->vfc_refcount;
3374 ovfs.vfc_flags = vfsp->vfc_flags;
3375 error = SYSCTL_OUT(req, &ovfs, sizeof ovfs);
3376 if (error != 0) {
3377 vfsconf_sunlock();
3378 return (error);
3379 }
3380 }
3381 vfsconf_sunlock();
3382 return (0);
3383 }
3384
3385 #endif /* 1 || COMPAT_PRELITE2 */
3386 #endif /* !BURN_BRIDGES */
3387
3388 #define KINFO_VNODESLOP 10
3389 #ifdef notyet
3390 /*
3391 * Dump vnode list (via sysctl).
3392 */
3393 /* ARGSUSED */
3394 static int
3395 sysctl_vnode(SYSCTL_HANDLER_ARGS)
3396 {
3397 struct xvnode *xvn;
3398 struct mount *mp;
3399 struct vnode *vp;
3400 int error, len, n;
3401
3402 /*
3403 * Stale numvnodes access is not fatal here.
3404 */
3405 req->lock = 0;
3406 len = (numvnodes + KINFO_VNODESLOP) * sizeof *xvn;
3407 if (!req->oldptr)
3408 /* Make an estimate */
3409 return (SYSCTL_OUT(req, 0, len));
3410
3411 error = sysctl_wire_old_buffer(req, 0);
3412 if (error != 0)
3413 return (error);
3414 xvn = malloc(len, M_TEMP, M_ZERO | M_WAITOK);
3415 n = 0;
3416 mtx_lock(&mountlist_mtx);
3417 TAILQ_FOREACH(mp, &mountlist, mnt_list) {
3418 if (vfs_busy(mp, MBF_NOWAIT | MBF_MNTLSTLOCK))
3419 continue;
3420 MNT_ILOCK(mp);
3421 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) {
3422 if (n == len)
3423 break;
3424 vref(vp);
3425 xvn[n].xv_size = sizeof *xvn;
3426 xvn[n].xv_vnode = vp;
3427 xvn[n].xv_id = 0; /* XXX compat */
3428 #define XV_COPY(field) xvn[n].xv_##field = vp->v_##field
3429 XV_COPY(usecount);
3430 XV_COPY(writecount);
3431 XV_COPY(holdcnt);
3432 XV_COPY(mount);
3433 XV_COPY(numoutput);
3434 XV_COPY(type);
3435 #undef XV_COPY
3436 xvn[n].xv_flag = vp->v_vflag;
3437
3438 switch (vp->v_type) {
3439 case VREG:
3440 case VDIR:
3441 case VLNK:
3442 break;
3443 case VBLK:
3444 case VCHR:
3445 if (vp->v_rdev == NULL) {
3446 vrele(vp);
3447 continue;
3448 }
3449 xvn[n].xv_dev = dev2udev(vp->v_rdev);
3450 break;
3451 case VSOCK:
3452 xvn[n].xv_socket = vp->v_socket;
3453 break;
3454 case VFIFO:
3455 xvn[n].xv_fifo = vp->v_fifoinfo;
3456 break;
3457 case VNON:
3458 case VBAD:
3459 default:
3460 /* shouldn't happen? */
3461 vrele(vp);
3462 continue;
3463 }
3464 vrele(vp);
3465 ++n;
3466 }
3467 MNT_IUNLOCK(mp);
3468 mtx_lock(&mountlist_mtx);
3469 vfs_unbusy(mp);
3470 if (n == len)
3471 break;
3472 }
3473 mtx_unlock(&mountlist_mtx);
3474
3475 error = SYSCTL_OUT(req, xvn, n * sizeof *xvn);
3476 free(xvn, M_TEMP);
3477 return (error);
3478 }
3479
3480 SYSCTL_PROC(_kern, KERN_VNODE, vnode, CTLTYPE_OPAQUE | CTLFLAG_RD |
3481 CTLFLAG_MPSAFE, 0, 0, sysctl_vnode, "S,xvnode",
3482 "");
3483 #endif
3484
3485 /*
3486 * Unmount all filesystems. The list is traversed in reverse order
3487 * of mounting to avoid dependencies.
3488 */
3489 void
3490 vfs_unmountall(void)
3491 {
3492 struct mount *mp;
3493 struct thread *td;
3494 int error;
3495
3496 CTR1(KTR_VFS, "%s: unmounting all filesystems", __func__);
3497 td = curthread;
3498
3499 /*
3500 * Since this only runs when rebooting, it is not interlocked.
3501 */
3502 while(!TAILQ_EMPTY(&mountlist)) {
3503 mp = TAILQ_LAST(&mountlist, mntlist);
3504 vfs_ref(mp);
3505 error = dounmount(mp, MNT_FORCE, td);
3506 if (error != 0) {
3507 TAILQ_REMOVE(&mountlist, mp, mnt_list);
3508 /*
3509 * XXX: Due to the way in which we mount the root
3510 * file system off of devfs, devfs will generate a
3511 * "busy" warning when we try to unmount it before
3512 * the root. Don't print a warning as a result in
3513 * order to avoid false positive errors that may
3514 * cause needless upset.
3515 */
3516 if (strcmp(mp->mnt_vfc->vfc_name, "devfs") != 0) {
3517 printf("unmount of %s failed (",
3518 mp->mnt_stat.f_mntonname);
3519 if (error == EBUSY)
3520 printf("BUSY)\n");
3521 else
3522 printf("%d)\n", error);
3523 }
3524 } else {
3525 /* The unmount has removed mp from the mountlist */
3526 }
3527 }
3528 }
3529
3530 /*
3531 * perform msync on all vnodes under a mount point
3532 * the mount point must be locked.
3533 */
3534 void
3535 vfs_msync(struct mount *mp, int flags)
3536 {
3537 struct vnode *vp, *mvp;
3538 struct vm_object *obj;
3539
3540 CTR2(KTR_VFS, "%s: mp %p", __func__, mp);
3541 MNT_VNODE_FOREACH_ACTIVE(vp, mp, mvp) {
3542 obj = vp->v_object;
3543 if (obj != NULL && (obj->flags & OBJ_MIGHTBEDIRTY) != 0 &&
3544 (flags == MNT_WAIT || VOP_ISLOCKED(vp) == 0)) {
3545 if (!vget(vp,
3546 LK_EXCLUSIVE | LK_RETRY | LK_INTERLOCK,
3547 curthread)) {
3548 if (vp->v_vflag & VV_NOSYNC) { /* unlinked */
3549 vput(vp);
3550 continue;
3551 }
3552
3553 obj = vp->v_object;
3554 if (obj != NULL) {
3555 VM_OBJECT_WLOCK(obj);
3556 vm_object_page_clean(obj, 0, 0,
3557 flags == MNT_WAIT ?
3558 OBJPC_SYNC : OBJPC_NOSYNC);
3559 VM_OBJECT_WUNLOCK(obj);
3560 }
3561 vput(vp);
3562 }
3563 } else
3564 VI_UNLOCK(vp);
3565 }
3566 }
3567
3568 static void
3569 destroy_vpollinfo_free(struct vpollinfo *vi)
3570 {
3571
3572 knlist_destroy(&vi->vpi_selinfo.si_note);
3573 mtx_destroy(&vi->vpi_lock);
3574 uma_zfree(vnodepoll_zone, vi);
3575 }
3576
3577 static void
3578 destroy_vpollinfo(struct vpollinfo *vi)
3579 {
3580
3581 knlist_clear(&vi->vpi_selinfo.si_note, 1);
3582 seldrain(&vi->vpi_selinfo);
3583 destroy_vpollinfo_free(vi);
3584 }
3585
3586 /*
3587 * Initalize per-vnode helper structure to hold poll-related state.
3588 */
3589 void
3590 v_addpollinfo(struct vnode *vp)
3591 {
3592 struct vpollinfo *vi;
3593
3594 if (vp->v_pollinfo != NULL)
3595 return;
3596 vi = uma_zalloc(vnodepoll_zone, M_WAITOK);
3597 mtx_init(&vi->vpi_lock, "vnode pollinfo", NULL, MTX_DEF);
3598 knlist_init(&vi->vpi_selinfo.si_note, vp, vfs_knllock,
3599 vfs_knlunlock, vfs_knl_assert_locked, vfs_knl_assert_unlocked);
3600 VI_LOCK(vp);
3601 if (vp->v_pollinfo != NULL) {
3602 VI_UNLOCK(vp);
3603 destroy_vpollinfo_free(vi);
3604 return;
3605 }
3606 vp->v_pollinfo = vi;
3607 VI_UNLOCK(vp);
3608 }
3609
3610 /*
3611 * Record a process's interest in events which might happen to
3612 * a vnode. Because poll uses the historic select-style interface
3613 * internally, this routine serves as both the ``check for any
3614 * pending events'' and the ``record my interest in future events''
3615 * functions. (These are done together, while the lock is held,
3616 * to avoid race conditions.)
3617 */
3618 int
3619 vn_pollrecord(struct vnode *vp, struct thread *td, int events)
3620 {
3621
3622 v_addpollinfo(vp);
3623 mtx_lock(&vp->v_pollinfo->vpi_lock);
3624 if (vp->v_pollinfo->vpi_revents & events) {
3625 /*
3626 * This leaves events we are not interested
3627 * in available for the other process which
3628 * which presumably had requested them
3629 * (otherwise they would never have been
3630 * recorded).
3631 */
3632 events &= vp->v_pollinfo->vpi_revents;
3633 vp->v_pollinfo->vpi_revents &= ~events;
3634
3635 mtx_unlock(&vp->v_pollinfo->vpi_lock);
3636 return (events);
3637 }
3638 vp->v_pollinfo->vpi_events |= events;
3639 selrecord(td, &vp->v_pollinfo->vpi_selinfo);
3640 mtx_unlock(&vp->v_pollinfo->vpi_lock);
3641 return (0);
3642 }
3643
3644 /*
3645 * Routine to create and manage a filesystem syncer vnode.
3646 */
3647 #define sync_close ((int (*)(struct vop_close_args *))nullop)
3648 static int sync_fsync(struct vop_fsync_args *);
3649 static int sync_inactive(struct vop_inactive_args *);
3650 static int sync_reclaim(struct vop_reclaim_args *);
3651
3652 static struct vop_vector sync_vnodeops = {
3653 .vop_bypass = VOP_EOPNOTSUPP,
3654 .vop_close = sync_close, /* close */
3655 .vop_fsync = sync_fsync, /* fsync */
3656 .vop_inactive = sync_inactive, /* inactive */
3657 .vop_reclaim = sync_reclaim, /* reclaim */
3658 .vop_lock1 = vop_stdlock, /* lock */
3659 .vop_unlock = vop_stdunlock, /* unlock */
3660 .vop_islocked = vop_stdislocked, /* islocked */
3661 };
3662
3663 /*
3664 * Create a new filesystem syncer vnode for the specified mount point.
3665 */
3666 void
3667 vfs_allocate_syncvnode(struct mount *mp)
3668 {
3669 struct vnode *vp;
3670 struct bufobj *bo;
3671 static long start, incr, next;
3672 int error;
3673
3674 /* Allocate a new vnode */
3675 error = getnewvnode("syncer", mp, &sync_vnodeops, &vp);
3676 if (error != 0)
3677 panic("vfs_allocate_syncvnode: getnewvnode() failed");
3678 vp->v_type = VNON;
3679 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
3680 vp->v_vflag |= VV_FORCEINSMQ;
3681 error = insmntque(vp, mp);
3682 if (error != 0)
3683 panic("vfs_allocate_syncvnode: insmntque() failed");
3684 vp->v_vflag &= ~VV_FORCEINSMQ;
3685 VOP_UNLOCK(vp, 0);
3686 /*
3687 * Place the vnode onto the syncer worklist. We attempt to
3688 * scatter them about on the list so that they will go off
3689 * at evenly distributed times even if all the filesystems
3690 * are mounted at once.
3691 */
3692 next += incr;
3693 if (next == 0 || next > syncer_maxdelay) {
3694 start /= 2;
3695 incr /= 2;
3696 if (start == 0) {
3697 start = syncer_maxdelay / 2;
3698 incr = syncer_maxdelay;
3699 }
3700 next = start;
3701 }
3702 bo = &vp->v_bufobj;
3703 BO_LOCK(bo);
3704 vn_syncer_add_to_worklist(bo, syncdelay > 0 ? next % syncdelay : 0);
3705 /* XXX - vn_syncer_add_to_worklist() also grabs and drops sync_mtx. */
3706 mtx_lock(&sync_mtx);
3707 sync_vnode_count++;
3708 if (mp->mnt_syncer == NULL) {
3709 mp->mnt_syncer = vp;
3710 vp = NULL;
3711 }
3712 mtx_unlock(&sync_mtx);
3713 BO_UNLOCK(bo);
3714 if (vp != NULL) {
3715 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
3716 vgone(vp);
3717 vput(vp);
3718 }
3719 }
3720
3721 void
3722 vfs_deallocate_syncvnode(struct mount *mp)
3723 {
3724 struct vnode *vp;
3725
3726 mtx_lock(&sync_mtx);
3727 vp = mp->mnt_syncer;
3728 if (vp != NULL)
3729 mp->mnt_syncer = NULL;
3730 mtx_unlock(&sync_mtx);
3731 if (vp != NULL)
3732 vrele(vp);
3733 }
3734
3735 /*
3736 * Do a lazy sync of the filesystem.
3737 */
3738 static int
3739 sync_fsync(struct vop_fsync_args *ap)
3740 {
3741 struct vnode *syncvp = ap->a_vp;
3742 struct mount *mp = syncvp->v_mount;
3743 int error, save;
3744 struct bufobj *bo;
3745
3746 /*
3747 * We only need to do something if this is a lazy evaluation.
3748 */
3749 if (ap->a_waitfor != MNT_LAZY)
3750 return (0);
3751
3752 /*
3753 * Move ourselves to the back of the sync list.
3754 */
3755 bo = &syncvp->v_bufobj;
3756 BO_LOCK(bo);
3757 vn_syncer_add_to_worklist(bo, syncdelay);
3758 BO_UNLOCK(bo);
3759
3760 /*
3761 * Walk the list of vnodes pushing all that are dirty and
3762 * not already on the sync list.
3763 */
3764 if (vfs_busy(mp, MBF_NOWAIT) != 0)
3765 return (0);
3766 if (vn_start_write(NULL, &mp, V_NOWAIT) != 0) {
3767 vfs_unbusy(mp);
3768 return (0);
3769 }
3770 save = curthread_pflags_set(TDP_SYNCIO);
3771 vfs_msync(mp, MNT_NOWAIT);
3772 error = VFS_SYNC(mp, MNT_LAZY);
3773 curthread_pflags_restore(save);
3774 vn_finished_write(mp);
3775 vfs_unbusy(mp);
3776 return (error);
3777 }
3778
3779 /*
3780 * The syncer vnode is no referenced.
3781 */
3782 static int
3783 sync_inactive(struct vop_inactive_args *ap)
3784 {
3785
3786 vgone(ap->a_vp);
3787 return (0);
3788 }
3789
3790 /*
3791 * The syncer vnode is no longer needed and is being decommissioned.
3792 *
3793 * Modifications to the worklist must be protected by sync_mtx.
3794 */
3795 static int
3796 sync_reclaim(struct vop_reclaim_args *ap)
3797 {
3798 struct vnode *vp = ap->a_vp;
3799 struct bufobj *bo;
3800
3801 bo = &vp->v_bufobj;
3802 BO_LOCK(bo);
3803 mtx_lock(&sync_mtx);
3804 if (vp->v_mount->mnt_syncer == vp)
3805 vp->v_mount->mnt_syncer = NULL;
3806 if (bo->bo_flag & BO_ONWORKLST) {
3807 LIST_REMOVE(bo, bo_synclist);
3808 syncer_worklist_len--;
3809 sync_vnode_count--;
3810 bo->bo_flag &= ~BO_ONWORKLST;
3811 }
3812 mtx_unlock(&sync_mtx);
3813 BO_UNLOCK(bo);
3814
3815 return (0);
3816 }
3817
3818 /*
3819 * Check if vnode represents a disk device
3820 */
3821 int
3822 vn_isdisk(struct vnode *vp, int *errp)
3823 {
3824 int error;
3825
3826 error = 0;
3827 dev_lock();
3828 if (vp->v_type != VCHR)
3829 error = ENOTBLK;
3830 else if (vp->v_rdev == NULL)
3831 error = ENXIO;
3832 else if (vp->v_rdev->si_devsw == NULL)
3833 error = ENXIO;
3834 else if (!(vp->v_rdev->si_devsw->d_flags & D_DISK))
3835 error = ENOTBLK;
3836 dev_unlock();
3837 if (errp != NULL)
3838 *errp = error;
3839 return (error == 0);
3840 }
3841
3842 /*
3843 * Common filesystem object access control check routine. Accepts a
3844 * vnode's type, "mode", uid and gid, requested access mode, credentials,
3845 * and optional call-by-reference privused argument allowing vaccess()
3846 * to indicate to the caller whether privilege was used to satisfy the
3847 * request (obsoleted). Returns 0 on success, or an errno on failure.
3848 */
3849 int
3850 vaccess(enum vtype type, mode_t file_mode, uid_t file_uid, gid_t file_gid,
3851 accmode_t accmode, struct ucred *cred, int *privused)
3852 {
3853 accmode_t dac_granted;
3854 accmode_t priv_granted;
3855
3856 KASSERT((accmode & ~(VEXEC | VWRITE | VREAD | VADMIN | VAPPEND)) == 0,
3857 ("invalid bit in accmode"));
3858 KASSERT((accmode & VAPPEND) == 0 || (accmode & VWRITE),
3859 ("VAPPEND without VWRITE"));
3860
3861 /*
3862 * Look for a normal, non-privileged way to access the file/directory
3863 * as requested. If it exists, go with that.
3864 */
3865
3866 if (privused != NULL)
3867 *privused = 0;
3868
3869 dac_granted = 0;
3870
3871 /* Check the owner. */
3872 if (cred->cr_uid == file_uid) {
3873 dac_granted |= VADMIN;
3874 if (file_mode & S_IXUSR)
3875 dac_granted |= VEXEC;
3876 if (file_mode & S_IRUSR)
3877 dac_granted |= VREAD;
3878 if (file_mode & S_IWUSR)
3879 dac_granted |= (VWRITE | VAPPEND);
3880
3881 if ((accmode & dac_granted) == accmode)
3882 return (0);
3883
3884 goto privcheck;
3885 }
3886
3887 /* Otherwise, check the groups (first match) */
3888 if (groupmember(file_gid, cred)) {
3889 if (file_mode & S_IXGRP)
3890 dac_granted |= VEXEC;
3891 if (file_mode & S_IRGRP)
3892 dac_granted |= VREAD;
3893 if (file_mode & S_IWGRP)
3894 dac_granted |= (VWRITE | VAPPEND);
3895
3896 if ((accmode & dac_granted) == accmode)
3897 return (0);
3898
3899 goto privcheck;
3900 }
3901
3902 /* Otherwise, check everyone else. */
3903 if (file_mode & S_IXOTH)
3904 dac_granted |= VEXEC;
3905 if (file_mode & S_IROTH)
3906 dac_granted |= VREAD;
3907 if (file_mode & S_IWOTH)
3908 dac_granted |= (VWRITE | VAPPEND);
3909 if ((accmode & dac_granted) == accmode)
3910 return (0);
3911
3912 privcheck:
3913 /*
3914 * Build a privilege mask to determine if the set of privileges
3915 * satisfies the requirements when combined with the granted mask
3916 * from above. For each privilege, if the privilege is required,
3917 * bitwise or the request type onto the priv_granted mask.
3918 */
3919 priv_granted = 0;
3920
3921 if (type == VDIR) {
3922 /*
3923 * For directories, use PRIV_VFS_LOOKUP to satisfy VEXEC
3924 * requests, instead of PRIV_VFS_EXEC.
3925 */
3926 if ((accmode & VEXEC) && ((dac_granted & VEXEC) == 0) &&
3927 !priv_check_cred(cred, PRIV_VFS_LOOKUP, 0))
3928 priv_granted |= VEXEC;
3929 } else {
3930 /*
3931 * Ensure that at least one execute bit is on. Otherwise,
3932 * a privileged user will always succeed, and we don't want
3933 * this to happen unless the file really is executable.
3934 */
3935 if ((accmode & VEXEC) && ((dac_granted & VEXEC) == 0) &&
3936 (file_mode & (S_IXUSR | S_IXGRP | S_IXOTH)) != 0 &&
3937 !priv_check_cred(cred, PRIV_VFS_EXEC, 0))
3938 priv_granted |= VEXEC;
3939 }
3940
3941 if ((accmode & VREAD) && ((dac_granted & VREAD) == 0) &&
3942 !priv_check_cred(cred, PRIV_VFS_READ, 0))
3943 priv_granted |= VREAD;
3944
3945 if ((accmode & VWRITE) && ((dac_granted & VWRITE) == 0) &&
3946 !priv_check_cred(cred, PRIV_VFS_WRITE, 0))
3947 priv_granted |= (VWRITE | VAPPEND);
3948
3949 if ((accmode & VADMIN) && ((dac_granted & VADMIN) == 0) &&
3950 !priv_check_cred(cred, PRIV_VFS_ADMIN, 0))
3951 priv_granted |= VADMIN;
3952
3953 if ((accmode & (priv_granted | dac_granted)) == accmode) {
3954 /* XXX audit: privilege used */
3955 if (privused != NULL)
3956 *privused = 1;
3957 return (0);
3958 }
3959
3960 return ((accmode & VADMIN) ? EPERM : EACCES);
3961 }
3962
3963 /*
3964 * Credential check based on process requesting service, and per-attribute
3965 * permissions.
3966 */
3967 int
3968 extattr_check_cred(struct vnode *vp, int attrnamespace, struct ucred *cred,
3969 struct thread *td, accmode_t accmode)
3970 {
3971
3972 /*
3973 * Kernel-invoked always succeeds.
3974 */
3975 if (cred == NOCRED)
3976 return (0);
3977
3978 /*
3979 * Do not allow privileged processes in jail to directly manipulate
3980 * system attributes.
3981 */
3982 switch (attrnamespace) {
3983 case EXTATTR_NAMESPACE_SYSTEM:
3984 /* Potentially should be: return (EPERM); */
3985 return (priv_check_cred(cred, PRIV_VFS_EXTATTR_SYSTEM, 0));
3986 case EXTATTR_NAMESPACE_USER:
3987 return (VOP_ACCESS(vp, accmode, cred, td));
3988 default:
3989 return (EPERM);
3990 }
3991 }
3992
3993 #ifdef DEBUG_VFS_LOCKS
3994 /*
3995 * This only exists to supress warnings from unlocked specfs accesses. It is
3996 * no longer ok to have an unlocked VFS.
3997 */
3998 #define IGNORE_LOCK(vp) (panicstr != NULL || (vp) == NULL || \
3999 (vp)->v_type == VCHR || (vp)->v_type == VBAD)
4000
4001 int vfs_badlock_ddb = 1; /* Drop into debugger on violation. */
4002 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_ddb, CTLFLAG_RW, &vfs_badlock_ddb, 0,
4003 "Drop into debugger on lock violation");
4004
4005 int vfs_badlock_mutex = 1; /* Check for interlock across VOPs. */
4006 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_mutex, CTLFLAG_RW, &vfs_badlock_mutex,
4007 0, "Check for interlock across VOPs");
4008
4009 int vfs_badlock_print = 1; /* Print lock violations. */
4010 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_print, CTLFLAG_RW, &vfs_badlock_print,
4011 0, "Print lock violations");
4012
4013 #ifdef KDB
4014 int vfs_badlock_backtrace = 1; /* Print backtrace at lock violations. */
4015 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_backtrace, CTLFLAG_RW,
4016 &vfs_badlock_backtrace, 0, "Print backtrace at lock violations");
4017 #endif
4018
4019 static void
4020 vfs_badlock(const char *msg, const char *str, struct vnode *vp)
4021 {
4022
4023 #ifdef KDB
4024 if (vfs_badlock_backtrace)
4025 kdb_backtrace();
4026 #endif
4027 if (vfs_badlock_print)
4028 printf("%s: %p %s\n", str, (void *)vp, msg);
4029 if (vfs_badlock_ddb)
4030 kdb_enter(KDB_WHY_VFSLOCK, "lock violation");
4031 }
4032
4033 void
4034 assert_vi_locked(struct vnode *vp, const char *str)
4035 {
4036
4037 if (vfs_badlock_mutex && !mtx_owned(VI_MTX(vp)))
4038 vfs_badlock("interlock is not locked but should be", str, vp);
4039 }
4040
4041 void
4042 assert_vi_unlocked(struct vnode *vp, const char *str)
4043 {
4044
4045 if (vfs_badlock_mutex && mtx_owned(VI_MTX(vp)))
4046 vfs_badlock("interlock is locked but should not be", str, vp);
4047 }
4048
4049 void
4050 assert_vop_locked(struct vnode *vp, const char *str)
4051 {
4052 int locked;
4053
4054 if (!IGNORE_LOCK(vp)) {
4055 locked = VOP_ISLOCKED(vp);
4056 if (locked == 0 || locked == LK_EXCLOTHER)
4057 vfs_badlock("is not locked but should be", str, vp);
4058 }
4059 }
4060
4061 void
4062 assert_vop_unlocked(struct vnode *vp, const char *str)
4063 {
4064
4065 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) == LK_EXCLUSIVE)
4066 vfs_badlock("is locked but should not be", str, vp);
4067 }
4068
4069 void
4070 assert_vop_elocked(struct vnode *vp, const char *str)
4071 {
4072
4073 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) != LK_EXCLUSIVE)
4074 vfs_badlock("is not exclusive locked but should be", str, vp);
4075 }
4076
4077 #if 0
4078 void
4079 assert_vop_elocked_other(struct vnode *vp, const char *str)
4080 {
4081
4082 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) != LK_EXCLOTHER)
4083 vfs_badlock("is not exclusive locked by another thread",
4084 str, vp);
4085 }
4086
4087 void
4088 assert_vop_slocked(struct vnode *vp, const char *str)
4089 {
4090
4091 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) != LK_SHARED)
4092 vfs_badlock("is not locked shared but should be", str, vp);
4093 }
4094 #endif /* 0 */
4095 #endif /* DEBUG_VFS_LOCKS */
4096
4097 void
4098 vop_rename_fail(struct vop_rename_args *ap)
4099 {
4100
4101 if (ap->a_tvp != NULL)
4102 vput(ap->a_tvp);
4103 if (ap->a_tdvp == ap->a_tvp)
4104 vrele(ap->a_tdvp);
4105 else
4106 vput(ap->a_tdvp);
4107 vrele(ap->a_fdvp);
4108 vrele(ap->a_fvp);
4109 }
4110
4111 void
4112 vop_rename_pre(void *ap)
4113 {
4114 struct vop_rename_args *a = ap;
4115
4116 #ifdef DEBUG_VFS_LOCKS
4117 if (a->a_tvp)
4118 ASSERT_VI_UNLOCKED(a->a_tvp, "VOP_RENAME");
4119 ASSERT_VI_UNLOCKED(a->a_tdvp, "VOP_RENAME");
4120 ASSERT_VI_UNLOCKED(a->a_fvp, "VOP_RENAME");
4121 ASSERT_VI_UNLOCKED(a->a_fdvp, "VOP_RENAME");
4122
4123 /* Check the source (from). */
4124 if (a->a_tdvp->v_vnlock != a->a_fdvp->v_vnlock &&
4125 (a->a_tvp == NULL || a->a_tvp->v_vnlock != a->a_fdvp->v_vnlock))
4126 ASSERT_VOP_UNLOCKED(a->a_fdvp, "vop_rename: fdvp locked");
4127 if (a->a_tvp == NULL || a->a_tvp->v_vnlock != a->a_fvp->v_vnlock)
4128 ASSERT_VOP_UNLOCKED(a->a_fvp, "vop_rename: fvp locked");
4129
4130 /* Check the target. */
4131 if (a->a_tvp)
4132 ASSERT_VOP_LOCKED(a->a_tvp, "vop_rename: tvp not locked");
4133 ASSERT_VOP_LOCKED(a->a_tdvp, "vop_rename: tdvp not locked");
4134 #endif
4135 if (a->a_tdvp != a->a_fdvp)
4136 vhold(a->a_fdvp);
4137 if (a->a_tvp != a->a_fvp)
4138 vhold(a->a_fvp);
4139 vhold(a->a_tdvp);
4140 if (a->a_tvp)
4141 vhold(a->a_tvp);
4142 }
4143
4144 void
4145 vop_strategy_pre(void *ap)
4146 {
4147 #ifdef DEBUG_VFS_LOCKS
4148 struct vop_strategy_args *a;
4149 struct buf *bp;
4150
4151 a = ap;
4152 bp = a->a_bp;
4153
4154 /*
4155 * Cluster ops lock their component buffers but not the IO container.
4156 */
4157 if ((bp->b_flags & B_CLUSTER) != 0)
4158 return;
4159
4160 if (panicstr == NULL && !BUF_ISLOCKED(bp)) {
4161 if (vfs_badlock_print)
4162 printf(
4163 "VOP_STRATEGY: bp is not locked but should be\n");
4164 if (vfs_badlock_ddb)
4165 kdb_enter(KDB_WHY_VFSLOCK, "lock violation");
4166 }
4167 #endif
4168 }
4169
4170 void
4171 vop_lock_pre(void *ap)
4172 {
4173 #ifdef DEBUG_VFS_LOCKS
4174 struct vop_lock1_args *a = ap;
4175
4176 if ((a->a_flags & LK_INTERLOCK) == 0)
4177 ASSERT_VI_UNLOCKED(a->a_vp, "VOP_LOCK");
4178 else
4179 ASSERT_VI_LOCKED(a->a_vp, "VOP_LOCK");
4180 #endif
4181 }
4182
4183 void
4184 vop_lock_post(void *ap, int rc)
4185 {
4186 #ifdef DEBUG_VFS_LOCKS
4187 struct vop_lock1_args *a = ap;
4188
4189 ASSERT_VI_UNLOCKED(a->a_vp, "VOP_LOCK");
4190 if (rc == 0 && (a->a_flags & LK_EXCLOTHER) == 0)
4191 ASSERT_VOP_LOCKED(a->a_vp, "VOP_LOCK");
4192 #endif
4193 }
4194
4195 void
4196 vop_unlock_pre(void *ap)
4197 {
4198 #ifdef DEBUG_VFS_LOCKS
4199 struct vop_unlock_args *a = ap;
4200
4201 if (a->a_flags & LK_INTERLOCK)
4202 ASSERT_VI_LOCKED(a->a_vp, "VOP_UNLOCK");
4203 ASSERT_VOP_LOCKED(a->a_vp, "VOP_UNLOCK");
4204 #endif
4205 }
4206
4207 void
4208 vop_unlock_post(void *ap, int rc)
4209 {
4210 #ifdef DEBUG_VFS_LOCKS
4211 struct vop_unlock_args *a = ap;
4212
4213 if (a->a_flags & LK_INTERLOCK)
4214 ASSERT_VI_UNLOCKED(a->a_vp, "VOP_UNLOCK");
4215 #endif
4216 }
4217
4218 void
4219 vop_create_post(void *ap, int rc)
4220 {
4221 struct vop_create_args *a = ap;
4222
4223 if (!rc)
4224 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE);
4225 }
4226
4227 void
4228 vop_deleteextattr_post(void *ap, int rc)
4229 {
4230 struct vop_deleteextattr_args *a = ap;
4231
4232 if (!rc)
4233 VFS_KNOTE_LOCKED(a->a_vp, NOTE_ATTRIB);
4234 }
4235
4236 void
4237 vop_link_post(void *ap, int rc)
4238 {
4239 struct vop_link_args *a = ap;
4240
4241 if (!rc) {
4242 VFS_KNOTE_LOCKED(a->a_vp, NOTE_LINK);
4243 VFS_KNOTE_LOCKED(a->a_tdvp, NOTE_WRITE);
4244 }
4245 }
4246
4247 void
4248 vop_mkdir_post(void *ap, int rc)
4249 {
4250 struct vop_mkdir_args *a = ap;
4251
4252 if (!rc)
4253 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE | NOTE_LINK);
4254 }
4255
4256 void
4257 vop_mknod_post(void *ap, int rc)
4258 {
4259 struct vop_mknod_args *a = ap;
4260
4261 if (!rc)
4262 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE);
4263 }
4264
4265 void
4266 vop_remove_post(void *ap, int rc)
4267 {
4268 struct vop_remove_args *a = ap;
4269
4270 if (!rc) {
4271 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE);
4272 VFS_KNOTE_LOCKED(a->a_vp, NOTE_DELETE);
4273 }
4274 }
4275
4276 void
4277 vop_rename_post(void *ap, int rc)
4278 {
4279 struct vop_rename_args *a = ap;
4280
4281 if (!rc) {
4282 VFS_KNOTE_UNLOCKED(a->a_fdvp, NOTE_WRITE);
4283 VFS_KNOTE_UNLOCKED(a->a_tdvp, NOTE_WRITE);
4284 VFS_KNOTE_UNLOCKED(a->a_fvp, NOTE_RENAME);
4285 if (a->a_tvp)
4286 VFS_KNOTE_UNLOCKED(a->a_tvp, NOTE_DELETE);
4287 }
4288 if (a->a_tdvp != a->a_fdvp)
4289 vdrop(a->a_fdvp);
4290 if (a->a_tvp != a->a_fvp)
4291 vdrop(a->a_fvp);
4292 vdrop(a->a_tdvp);
4293 if (a->a_tvp)
4294 vdrop(a->a_tvp);
4295 }
4296
4297 void
4298 vop_rmdir_post(void *ap, int rc)
4299 {
4300 struct vop_rmdir_args *a = ap;
4301
4302 if (!rc) {
4303 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE | NOTE_LINK);
4304 VFS_KNOTE_LOCKED(a->a_vp, NOTE_DELETE);
4305 }
4306 }
4307
4308 void
4309 vop_setattr_post(void *ap, int rc)
4310 {
4311 struct vop_setattr_args *a = ap;
4312
4313 if (!rc)
4314 VFS_KNOTE_LOCKED(a->a_vp, NOTE_ATTRIB);
4315 }
4316
4317 void
4318 vop_setextattr_post(void *ap, int rc)
4319 {
4320 struct vop_setextattr_args *a = ap;
4321
4322 if (!rc)
4323 VFS_KNOTE_LOCKED(a->a_vp, NOTE_ATTRIB);
4324 }
4325
4326 void
4327 vop_symlink_post(void *ap, int rc)
4328 {
4329 struct vop_symlink_args *a = ap;
4330
4331 if (!rc)
4332 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE);
4333 }
4334
4335 static struct knlist fs_knlist;
4336
4337 static void
4338 vfs_event_init(void *arg)
4339 {
4340 knlist_init_mtx(&fs_knlist, NULL);
4341 }
4342 /* XXX - correct order? */
4343 SYSINIT(vfs_knlist, SI_SUB_VFS, SI_ORDER_ANY, vfs_event_init, NULL);
4344
4345 void
4346 vfs_event_signal(fsid_t *fsid, uint32_t event, intptr_t data __unused)
4347 {
4348
4349 KNOTE_UNLOCKED(&fs_knlist, event);
4350 }
4351
4352 static int filt_fsattach(struct knote *kn);
4353 static void filt_fsdetach(struct knote *kn);
4354 static int filt_fsevent(struct knote *kn, long hint);
4355
4356 struct filterops fs_filtops = {
4357 .f_isfd = 0,
4358 .f_attach = filt_fsattach,
4359 .f_detach = filt_fsdetach,
4360 .f_event = filt_fsevent
4361 };
4362
4363 static int
4364 filt_fsattach(struct knote *kn)
4365 {
4366
4367 kn->kn_flags |= EV_CLEAR;
4368 knlist_add(&fs_knlist, kn, 0);
4369 return (0);
4370 }
4371
4372 static void
4373 filt_fsdetach(struct knote *kn)
4374 {
4375
4376 knlist_remove(&fs_knlist, kn, 0);
4377 }
4378
4379 static int
4380 filt_fsevent(struct knote *kn, long hint)
4381 {
4382
4383 kn->kn_fflags |= hint;
4384 return (kn->kn_fflags != 0);
4385 }
4386
4387 static int
4388 sysctl_vfs_ctl(SYSCTL_HANDLER_ARGS)
4389 {
4390 struct vfsidctl vc;
4391 int error;
4392 struct mount *mp;
4393
4394 error = SYSCTL_IN(req, &vc, sizeof(vc));
4395 if (error)
4396 return (error);
4397 if (vc.vc_vers != VFS_CTL_VERS1)
4398 return (EINVAL);
4399 mp = vfs_getvfs(&vc.vc_fsid);
4400 if (mp == NULL)
4401 return (ENOENT);
4402 /* ensure that a specific sysctl goes to the right filesystem. */
4403 if (strcmp(vc.vc_fstypename, "*") != 0 &&
4404 strcmp(vc.vc_fstypename, mp->mnt_vfc->vfc_name) != 0) {
4405 vfs_rel(mp);
4406 return (EINVAL);
4407 }
4408 VCTLTOREQ(&vc, req);
4409 error = VFS_SYSCTL(mp, vc.vc_op, req);
4410 vfs_rel(mp);
4411 return (error);
4412 }
4413
4414 SYSCTL_PROC(_vfs, OID_AUTO, ctl, CTLTYPE_OPAQUE | CTLFLAG_WR,
4415 NULL, 0, sysctl_vfs_ctl, "",
4416 "Sysctl by fsid");
4417
4418 /*
4419 * Function to initialize a va_filerev field sensibly.
4420 * XXX: Wouldn't a random number make a lot more sense ??
4421 */
4422 u_quad_t
4423 init_va_filerev(void)
4424 {
4425 struct bintime bt;
4426
4427 getbinuptime(&bt);
4428 return (((u_quad_t)bt.sec << 32LL) | (bt.frac >> 32LL));
4429 }
4430
4431 static int filt_vfsread(struct knote *kn, long hint);
4432 static int filt_vfswrite(struct knote *kn, long hint);
4433 static int filt_vfsvnode(struct knote *kn, long hint);
4434 static void filt_vfsdetach(struct knote *kn);
4435 static struct filterops vfsread_filtops = {
4436 .f_isfd = 1,
4437 .f_detach = filt_vfsdetach,
4438 .f_event = filt_vfsread
4439 };
4440 static struct filterops vfswrite_filtops = {
4441 .f_isfd = 1,
4442 .f_detach = filt_vfsdetach,
4443 .f_event = filt_vfswrite
4444 };
4445 static struct filterops vfsvnode_filtops = {
4446 .f_isfd = 1,
4447 .f_detach = filt_vfsdetach,
4448 .f_event = filt_vfsvnode
4449 };
4450
4451 static void
4452 vfs_knllock(void *arg)
4453 {
4454 struct vnode *vp = arg;
4455
4456 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
4457 }
4458
4459 static void
4460 vfs_knlunlock(void *arg)
4461 {
4462 struct vnode *vp = arg;
4463
4464 VOP_UNLOCK(vp, 0);
4465 }
4466
4467 static void
4468 vfs_knl_assert_locked(void *arg)
4469 {
4470 #ifdef DEBUG_VFS_LOCKS
4471 struct vnode *vp = arg;
4472
4473 ASSERT_VOP_LOCKED(vp, "vfs_knl_assert_locked");
4474 #endif
4475 }
4476
4477 static void
4478 vfs_knl_assert_unlocked(void *arg)
4479 {
4480 #ifdef DEBUG_VFS_LOCKS
4481 struct vnode *vp = arg;
4482
4483 ASSERT_VOP_UNLOCKED(vp, "vfs_knl_assert_unlocked");
4484 #endif
4485 }
4486
4487 int
4488 vfs_kqfilter(struct vop_kqfilter_args *ap)
4489 {
4490 struct vnode *vp = ap->a_vp;
4491 struct knote *kn = ap->a_kn;
4492 struct knlist *knl;
4493
4494 switch (kn->kn_filter) {
4495 case EVFILT_READ:
4496 kn->kn_fop = &vfsread_filtops;
4497 break;
4498 case EVFILT_WRITE:
4499 kn->kn_fop = &vfswrite_filtops;
4500 break;
4501 case EVFILT_VNODE:
4502 kn->kn_fop = &vfsvnode_filtops;
4503 break;
4504 default:
4505 return (EINVAL);
4506 }
4507
4508 kn->kn_hook = (caddr_t)vp;
4509
4510 v_addpollinfo(vp);
4511 if (vp->v_pollinfo == NULL)
4512 return (ENOMEM);
4513 knl = &vp->v_pollinfo->vpi_selinfo.si_note;
4514 vhold(vp);
4515 knlist_add(knl, kn, 0);
4516
4517 return (0);
4518 }
4519
4520 /*
4521 * Detach knote from vnode
4522 */
4523 static void
4524 filt_vfsdetach(struct knote *kn)
4525 {
4526 struct vnode *vp = (struct vnode *)kn->kn_hook;
4527
4528 KASSERT(vp->v_pollinfo != NULL, ("Missing v_pollinfo"));
4529 knlist_remove(&vp->v_pollinfo->vpi_selinfo.si_note, kn, 0);
4530 vdrop(vp);
4531 }
4532
4533 /*ARGSUSED*/
4534 static int
4535 filt_vfsread(struct knote *kn, long hint)
4536 {
4537 struct vnode *vp = (struct vnode *)kn->kn_hook;
4538 struct vattr va;
4539 int res;
4540
4541 /*
4542 * filesystem is gone, so set the EOF flag and schedule
4543 * the knote for deletion.
4544 */
4545 if (hint == NOTE_REVOKE) {
4546 VI_LOCK(vp);
4547 kn->kn_flags |= (EV_EOF | EV_ONESHOT);
4548 VI_UNLOCK(vp);
4549 return (1);
4550 }
4551
4552 if (VOP_GETATTR(vp, &va, curthread->td_ucred))
4553 return (0);
4554
4555 VI_LOCK(vp);
4556 kn->kn_data = va.va_size - kn->kn_fp->f_offset;
4557 res = (kn->kn_data != 0);
4558 VI_UNLOCK(vp);
4559 return (res);
4560 }
4561
4562 /*ARGSUSED*/
4563 static int
4564 filt_vfswrite(struct knote *kn, long hint)
4565 {
4566 struct vnode *vp = (struct vnode *)kn->kn_hook;
4567
4568 VI_LOCK(vp);
4569
4570 /*
4571 * filesystem is gone, so set the EOF flag and schedule
4572 * the knote for deletion.
4573 */
4574 if (hint == NOTE_REVOKE)
4575 kn->kn_flags |= (EV_EOF | EV_ONESHOT);
4576
4577 kn->kn_data = 0;
4578 VI_UNLOCK(vp);
4579 return (1);
4580 }
4581
4582 static int
4583 filt_vfsvnode(struct knote *kn, long hint)
4584 {
4585 struct vnode *vp = (struct vnode *)kn->kn_hook;
4586 int res;
4587
4588 VI_LOCK(vp);
4589 if (kn->kn_sfflags & hint)
4590 kn->kn_fflags |= hint;
4591 if (hint == NOTE_REVOKE) {
4592 kn->kn_flags |= EV_EOF;
4593 VI_UNLOCK(vp);
4594 return (1);
4595 }
4596 res = (kn->kn_fflags != 0);
4597 VI_UNLOCK(vp);
4598 return (res);
4599 }
4600
4601 int
4602 vfs_read_dirent(struct vop_readdir_args *ap, struct dirent *dp, off_t off)
4603 {
4604 int error;
4605
4606 if (dp->d_reclen > ap->a_uio->uio_resid)
4607 return (ENAMETOOLONG);
4608 error = uiomove(dp, dp->d_reclen, ap->a_uio);
4609 if (error) {
4610 if (ap->a_ncookies != NULL) {
4611 if (ap->a_cookies != NULL)
4612 free(ap->a_cookies, M_TEMP);
4613 ap->a_cookies = NULL;
4614 *ap->a_ncookies = 0;
4615 }
4616 return (error);
4617 }
4618 if (ap->a_ncookies == NULL)
4619 return (0);
4620
4621 KASSERT(ap->a_cookies,
4622 ("NULL ap->a_cookies value with non-NULL ap->a_ncookies!"));
4623
4624 *ap->a_cookies = realloc(*ap->a_cookies,
4625 (*ap->a_ncookies + 1) * sizeof(u_long), M_TEMP, M_WAITOK | M_ZERO);
4626 (*ap->a_cookies)[*ap->a_ncookies] = off;
4627 return (0);
4628 }
4629
4630 /*
4631 * Mark for update the access time of the file if the filesystem
4632 * supports VOP_MARKATIME. This functionality is used by execve and
4633 * mmap, so we want to avoid the I/O implied by directly setting
4634 * va_atime for the sake of efficiency.
4635 */
4636 void
4637 vfs_mark_atime(struct vnode *vp, struct ucred *cred)
4638 {
4639 struct mount *mp;
4640
4641 mp = vp->v_mount;
4642 ASSERT_VOP_LOCKED(vp, "vfs_mark_atime");
4643 if (mp != NULL && (mp->mnt_flag & (MNT_NOATIME | MNT_RDONLY)) == 0)
4644 (void)VOP_MARKATIME(vp);
4645 }
4646
4647 /*
4648 * The purpose of this routine is to remove granularity from accmode_t,
4649 * reducing it into standard unix access bits - VEXEC, VREAD, VWRITE,
4650 * VADMIN and VAPPEND.
4651 *
4652 * If it returns 0, the caller is supposed to continue with the usual
4653 * access checks using 'accmode' as modified by this routine. If it
4654 * returns nonzero value, the caller is supposed to return that value
4655 * as errno.
4656 *
4657 * Note that after this routine runs, accmode may be zero.
4658 */
4659 int
4660 vfs_unixify_accmode(accmode_t *accmode)
4661 {
4662 /*
4663 * There is no way to specify explicit "deny" rule using
4664 * file mode or POSIX.1e ACLs.
4665 */
4666 if (*accmode & VEXPLICIT_DENY) {
4667 *accmode = 0;
4668 return (0);
4669 }
4670
4671 /*
4672 * None of these can be translated into usual access bits.
4673 * Also, the common case for NFSv4 ACLs is to not contain
4674 * either of these bits. Caller should check for VWRITE
4675 * on the containing directory instead.
4676 */
4677 if (*accmode & (VDELETE_CHILD | VDELETE))
4678 return (EPERM);
4679
4680 if (*accmode & VADMIN_PERMS) {
4681 *accmode &= ~VADMIN_PERMS;
4682 *accmode |= VADMIN;
4683 }
4684
4685 /*
4686 * There is no way to deny VREAD_ATTRIBUTES, VREAD_ACL
4687 * or VSYNCHRONIZE using file mode or POSIX.1e ACL.
4688 */
4689 *accmode &= ~(VSTAT_PERMS | VSYNCHRONIZE);
4690
4691 return (0);
4692 }
4693
4694 /*
4695 * These are helper functions for filesystems to traverse all
4696 * their vnodes. See MNT_VNODE_FOREACH_ALL() in sys/mount.h.
4697 *
4698 * This interface replaces MNT_VNODE_FOREACH.
4699 */
4700
4701 MALLOC_DEFINE(M_VNODE_MARKER, "vnodemarker", "vnode marker");
4702
4703 struct vnode *
4704 __mnt_vnode_next_all(struct vnode **mvp, struct mount *mp)
4705 {
4706 struct vnode *vp;
4707
4708 if (should_yield())
4709 kern_yield(PRI_USER);
4710 MNT_ILOCK(mp);
4711 KASSERT((*mvp)->v_mount == mp, ("marker vnode mount list mismatch"));
4712 vp = TAILQ_NEXT(*mvp, v_nmntvnodes);
4713 while (vp != NULL && (vp->v_type == VMARKER ||
4714 (vp->v_iflag & VI_DOOMED) != 0))
4715 vp = TAILQ_NEXT(vp, v_nmntvnodes);
4716
4717 /* Check if we are done */
4718 if (vp == NULL) {
4719 __mnt_vnode_markerfree_all(mvp, mp);
4720 /* MNT_IUNLOCK(mp); -- done in above function */
4721 mtx_assert(MNT_MTX(mp), MA_NOTOWNED);
4722 return (NULL);
4723 }
4724 TAILQ_REMOVE(&mp->mnt_nvnodelist, *mvp, v_nmntvnodes);
4725 TAILQ_INSERT_AFTER(&mp->mnt_nvnodelist, vp, *mvp, v_nmntvnodes);
4726 VI_LOCK(vp);
4727 MNT_IUNLOCK(mp);
4728 return (vp);
4729 }
4730
4731 struct vnode *
4732 __mnt_vnode_first_all(struct vnode **mvp, struct mount *mp)
4733 {
4734 struct vnode *vp;
4735
4736 *mvp = malloc(sizeof(struct vnode), M_VNODE_MARKER, M_WAITOK | M_ZERO);
4737 MNT_ILOCK(mp);
4738 MNT_REF(mp);
4739 (*mvp)->v_type = VMARKER;
4740
4741 vp = TAILQ_FIRST(&mp->mnt_nvnodelist);
4742 while (vp != NULL && (vp->v_type == VMARKER ||
4743 (vp->v_iflag & VI_DOOMED) != 0))
4744 vp = TAILQ_NEXT(vp, v_nmntvnodes);
4745
4746 /* Check if we are done */
4747 if (vp == NULL) {
4748 MNT_REL(mp);
4749 MNT_IUNLOCK(mp);
4750 free(*mvp, M_VNODE_MARKER);
4751 *mvp = NULL;
4752 return (NULL);
4753 }
4754 (*mvp)->v_mount = mp;
4755 TAILQ_INSERT_AFTER(&mp->mnt_nvnodelist, vp, *mvp, v_nmntvnodes);
4756 VI_LOCK(vp);
4757 MNT_IUNLOCK(mp);
4758 return (vp);
4759 }
4760
4761
4762 void
4763 __mnt_vnode_markerfree_all(struct vnode **mvp, struct mount *mp)
4764 {
4765
4766 if (*mvp == NULL) {
4767 MNT_IUNLOCK(mp);
4768 return;
4769 }
4770
4771 mtx_assert(MNT_MTX(mp), MA_OWNED);
4772
4773 KASSERT((*mvp)->v_mount == mp, ("marker vnode mount list mismatch"));
4774 TAILQ_REMOVE(&mp->mnt_nvnodelist, *mvp, v_nmntvnodes);
4775 MNT_REL(mp);
4776 MNT_IUNLOCK(mp);
4777 free(*mvp, M_VNODE_MARKER);
4778 *mvp = NULL;
4779 }
4780
4781 /*
4782 * These are helper functions for filesystems to traverse their
4783 * active vnodes. See MNT_VNODE_FOREACH_ACTIVE() in sys/mount.h
4784 */
4785 static void
4786 mnt_vnode_markerfree_active(struct vnode **mvp, struct mount *mp)
4787 {
4788
4789 KASSERT((*mvp)->v_mount == mp, ("marker vnode mount list mismatch"));
4790
4791 MNT_ILOCK(mp);
4792 MNT_REL(mp);
4793 MNT_IUNLOCK(mp);
4794 free(*mvp, M_VNODE_MARKER);
4795 *mvp = NULL;
4796 }
4797
4798 static struct vnode *
4799 mnt_vnode_next_active(struct vnode **mvp, struct mount *mp)
4800 {
4801 struct vnode *vp, *nvp;
4802
4803 mtx_assert(&vnode_free_list_mtx, MA_OWNED);
4804 KASSERT((*mvp)->v_mount == mp, ("marker vnode mount list mismatch"));
4805 restart:
4806 vp = TAILQ_NEXT(*mvp, v_actfreelist);
4807 TAILQ_REMOVE(&mp->mnt_activevnodelist, *mvp, v_actfreelist);
4808 while (vp != NULL) {
4809 if (vp->v_type == VMARKER) {
4810 vp = TAILQ_NEXT(vp, v_actfreelist);
4811 continue;
4812 }
4813 if (!VI_TRYLOCK(vp)) {
4814 if (mp_ncpus == 1 || should_yield()) {
4815 TAILQ_INSERT_BEFORE(vp, *mvp, v_actfreelist);
4816 mtx_unlock(&vnode_free_list_mtx);
4817 pause("vnacti", 1);
4818 mtx_lock(&vnode_free_list_mtx);
4819 goto restart;
4820 }
4821 continue;
4822 }
4823 KASSERT(vp->v_type != VMARKER, ("locked marker %p", vp));
4824 KASSERT(vp->v_mount == mp || vp->v_mount == NULL,
4825 ("alien vnode on the active list %p %p", vp, mp));
4826 if (vp->v_mount == mp && (vp->v_iflag & VI_DOOMED) == 0)
4827 break;
4828 nvp = TAILQ_NEXT(vp, v_actfreelist);
4829 VI_UNLOCK(vp);
4830 vp = nvp;
4831 }
4832
4833 /* Check if we are done */
4834 if (vp == NULL) {
4835 mtx_unlock(&vnode_free_list_mtx);
4836 mnt_vnode_markerfree_active(mvp, mp);
4837 return (NULL);
4838 }
4839 TAILQ_INSERT_AFTER(&mp->mnt_activevnodelist, vp, *mvp, v_actfreelist);
4840 mtx_unlock(&vnode_free_list_mtx);
4841 ASSERT_VI_LOCKED(vp, "active iter");
4842 KASSERT((vp->v_iflag & VI_ACTIVE) != 0, ("Non-active vp %p", vp));
4843 return (vp);
4844 }
4845
4846 struct vnode *
4847 __mnt_vnode_next_active(struct vnode **mvp, struct mount *mp)
4848 {
4849
4850 if (should_yield())
4851 kern_yield(PRI_USER);
4852 mtx_lock(&vnode_free_list_mtx);
4853 return (mnt_vnode_next_active(mvp, mp));
4854 }
4855
4856 struct vnode *
4857 __mnt_vnode_first_active(struct vnode **mvp, struct mount *mp)
4858 {
4859 struct vnode *vp;
4860
4861 *mvp = malloc(sizeof(struct vnode), M_VNODE_MARKER, M_WAITOK | M_ZERO);
4862 MNT_ILOCK(mp);
4863 MNT_REF(mp);
4864 MNT_IUNLOCK(mp);
4865 (*mvp)->v_type = VMARKER;
4866 (*mvp)->v_mount = mp;
4867
4868 mtx_lock(&vnode_free_list_mtx);
4869 vp = TAILQ_FIRST(&mp->mnt_activevnodelist);
4870 if (vp == NULL) {
4871 mtx_unlock(&vnode_free_list_mtx);
4872 mnt_vnode_markerfree_active(mvp, mp);
4873 return (NULL);
4874 }
4875 TAILQ_INSERT_BEFORE(vp, *mvp, v_actfreelist);
4876 return (mnt_vnode_next_active(mvp, mp));
4877 }
4878
4879 void
4880 __mnt_vnode_markerfree_active(struct vnode **mvp, struct mount *mp)
4881 {
4882
4883 if (*mvp == NULL)
4884 return;
4885
4886 mtx_lock(&vnode_free_list_mtx);
4887 TAILQ_REMOVE(&mp->mnt_activevnodelist, *mvp, v_actfreelist);
4888 mtx_unlock(&vnode_free_list_mtx);
4889 mnt_vnode_markerfree_active(mvp, mp);
4890 }
Cache object: 7f3031227b25587e11657ba027f04a2e
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