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("$FreeBSD$");
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/priv.h>
69 #include <sys/reboot.h>
70 #include <sys/sched.h>
71 #include <sys/sleepqueue.h>
72 #include <sys/smp.h>
73 #include <sys/stat.h>
74 #include <sys/sysctl.h>
75 #include <sys/syslog.h>
76 #include <sys/vmmeter.h>
77 #include <sys/vnode.h>
78 #include <sys/watchdog.h>
79
80 #include <machine/stdarg.h>
81
82 #include <security/mac/mac_framework.h>
83
84 #include <vm/vm.h>
85 #include <vm/vm_object.h>
86 #include <vm/vm_extern.h>
87 #include <vm/pmap.h>
88 #include <vm/vm_map.h>
89 #include <vm/vm_page.h>
90 #include <vm/vm_kern.h>
91 #include <vm/uma.h>
92
93 #ifdef DDB
94 #include <ddb/ddb.h>
95 #endif
96
97 #define WI_MPSAFEQ 0
98 #define WI_GIANTQ 1
99
100 static void delmntque(struct vnode *vp);
101 static int flushbuflist(struct bufv *bufv, int flags, struct bufobj *bo,
102 int slpflag, int slptimeo);
103 static void syncer_shutdown(void *arg, int howto);
104 static int vtryrecycle(struct vnode *vp);
105 static void v_incr_usecount(struct vnode *);
106 static void v_decr_usecount(struct vnode *);
107 static void v_decr_useonly(struct vnode *);
108 static void v_upgrade_usecount(struct vnode *);
109 static void vnlru_free(int);
110 static void vgonel(struct vnode *);
111 static void vfs_knllock(void *arg);
112 static void vfs_knlunlock(void *arg);
113 static void vfs_knl_assert_locked(void *arg);
114 static void vfs_knl_assert_unlocked(void *arg);
115 static void destroy_vpollinfo(struct vpollinfo *vi);
116
117 /*
118 * Number of vnodes in existence. Increased whenever getnewvnode()
119 * allocates a new vnode, decreased in vdropl() for VI_DOOMED vnode.
120 */
121 static unsigned long numvnodes;
122
123 SYSCTL_ULONG(_vfs, OID_AUTO, numvnodes, CTLFLAG_RD, &numvnodes, 0,
124 "Number of vnodes in existence");
125
126 static u_long vnodes_created;
127 SYSCTL_ULONG(_vfs, OID_AUTO, vnodes_created, CTLFLAG_RD, &vnodes_created,
128 0, "Number of vnodes created by getnewvnode");
129
130 /*
131 * Conversion tables for conversion from vnode types to inode formats
132 * and back.
133 */
134 enum vtype iftovt_tab[16] = {
135 VNON, VFIFO, VCHR, VNON, VDIR, VNON, VBLK, VNON,
136 VREG, VNON, VLNK, VNON, VSOCK, VNON, VNON, VBAD,
137 };
138 int vttoif_tab[10] = {
139 0, S_IFREG, S_IFDIR, S_IFBLK, S_IFCHR, S_IFLNK,
140 S_IFSOCK, S_IFIFO, S_IFMT, S_IFMT
141 };
142
143 /*
144 * List of vnodes that are ready for recycling.
145 */
146 static TAILQ_HEAD(freelst, vnode) vnode_free_list;
147
148 /*
149 * Free vnode target. Free vnodes may simply be files which have been stat'd
150 * but not read. This is somewhat common, and a small cache of such files
151 * should be kept to avoid recreation costs.
152 */
153 static u_long wantfreevnodes;
154 SYSCTL_ULONG(_vfs, OID_AUTO, wantfreevnodes, CTLFLAG_RW, &wantfreevnodes, 0, "");
155 /* Number of vnodes in the free list. */
156 static u_long freevnodes;
157 SYSCTL_ULONG(_vfs, OID_AUTO, freevnodes, CTLFLAG_RD, &freevnodes, 0,
158 "Number of vnodes in the free list");
159
160 static int vlru_allow_cache_src;
161 SYSCTL_INT(_vfs, OID_AUTO, vlru_allow_cache_src, CTLFLAG_RW,
162 &vlru_allow_cache_src, 0, "Allow vlru to reclaim source vnode");
163
164 static u_long recycles_count;
165 SYSCTL_ULONG(_vfs, OID_AUTO, recycles, CTLFLAG_RD, &recycles_count, 0,
166 "Number of vnodes recycled to avoid exceding kern.maxvnodes");
167
168 /*
169 * Various variables used for debugging the new implementation of
170 * reassignbuf().
171 * XXX these are probably of (very) limited utility now.
172 */
173 static int reassignbufcalls;
174 SYSCTL_INT(_vfs, OID_AUTO, reassignbufcalls, CTLFLAG_RW, &reassignbufcalls, 0,
175 "Number of calls to reassignbuf");
176
177 /*
178 * Cache for the mount type id assigned to NFS. This is used for
179 * special checks in nfs/nfs_nqlease.c and vm/vnode_pager.c.
180 */
181 int nfs_mount_type = -1;
182
183 /* To keep more than one thread at a time from running vfs_getnewfsid */
184 static struct mtx mntid_mtx;
185
186 /*
187 * Lock for any access to the following:
188 * vnode_free_list
189 * numvnodes
190 * freevnodes
191 */
192 static struct mtx vnode_free_list_mtx;
193
194 /* Publicly exported FS */
195 struct nfs_public nfs_pub;
196
197 /* Zone for allocation of new vnodes - used exclusively by getnewvnode() */
198 static uma_zone_t vnode_zone;
199 static uma_zone_t vnodepoll_zone;
200
201 /*
202 * The workitem queue.
203 *
204 * It is useful to delay writes of file data and filesystem metadata
205 * for tens of seconds so that quickly created and deleted files need
206 * not waste disk bandwidth being created and removed. To realize this,
207 * we append vnodes to a "workitem" queue. When running with a soft
208 * updates implementation, most pending metadata dependencies should
209 * not wait for more than a few seconds. Thus, mounted on block devices
210 * are delayed only about a half the time that file data is delayed.
211 * Similarly, directory updates are more critical, so are only delayed
212 * about a third the time that file data is delayed. Thus, there are
213 * SYNCER_MAXDELAY queues that are processed round-robin at a rate of
214 * one each second (driven off the filesystem syncer process). The
215 * syncer_delayno variable indicates the next queue that is to be processed.
216 * Items that need to be processed soon are placed in this queue:
217 *
218 * syncer_workitem_pending[syncer_delayno]
219 *
220 * A delay of fifteen seconds is done by placing the request fifteen
221 * entries later in the queue:
222 *
223 * syncer_workitem_pending[(syncer_delayno + 15) & syncer_mask]
224 *
225 */
226 static int syncer_delayno;
227 static long syncer_mask;
228 LIST_HEAD(synclist, bufobj);
229 static struct synclist *syncer_workitem_pending[2];
230 /*
231 * The sync_mtx protects:
232 * bo->bo_synclist
233 * sync_vnode_count
234 * syncer_delayno
235 * syncer_state
236 * syncer_workitem_pending
237 * syncer_worklist_len
238 * rushjob
239 */
240 static struct mtx sync_mtx;
241 static struct cv sync_wakeup;
242
243 #define SYNCER_MAXDELAY 32
244 static int syncer_maxdelay = SYNCER_MAXDELAY; /* maximum delay time */
245 static int syncdelay = 30; /* max time to delay syncing data */
246 static int filedelay = 30; /* time to delay syncing files */
247 SYSCTL_INT(_kern, OID_AUTO, filedelay, CTLFLAG_RW, &filedelay, 0,
248 "Time to delay syncing files (in seconds)");
249 static int dirdelay = 29; /* time to delay syncing directories */
250 SYSCTL_INT(_kern, OID_AUTO, dirdelay, CTLFLAG_RW, &dirdelay, 0,
251 "Time to delay syncing directories (in seconds)");
252 static int metadelay = 28; /* time to delay syncing metadata */
253 SYSCTL_INT(_kern, OID_AUTO, metadelay, CTLFLAG_RW, &metadelay, 0,
254 "Time to delay syncing metadata (in seconds)");
255 static int rushjob; /* number of slots to run ASAP */
256 static int stat_rush_requests; /* number of times I/O speeded up */
257 SYSCTL_INT(_debug, OID_AUTO, rush_requests, CTLFLAG_RW, &stat_rush_requests, 0,
258 "Number of times I/O speeded up (rush requests)");
259
260 /*
261 * When shutting down the syncer, run it at four times normal speed.
262 */
263 #define SYNCER_SHUTDOWN_SPEEDUP 4
264 static int sync_vnode_count;
265 static int syncer_worklist_len;
266 static enum { SYNCER_RUNNING, SYNCER_SHUTTING_DOWN, SYNCER_FINAL_DELAY }
267 syncer_state;
268
269 /*
270 * Number of vnodes we want to exist at any one time. This is mostly used
271 * to size hash tables in vnode-related code. It is normally not used in
272 * getnewvnode(), as wantfreevnodes is normally nonzero.)
273 *
274 * XXX desiredvnodes is historical cruft and should not exist.
275 */
276 int desiredvnodes;
277 SYSCTL_INT(_kern, KERN_MAXVNODES, maxvnodes, CTLFLAG_RW,
278 &desiredvnodes, 0, "Maximum number of vnodes");
279 SYSCTL_ULONG(_kern, OID_AUTO, minvnodes, CTLFLAG_RW,
280 &wantfreevnodes, 0, "Minimum number of vnodes (legacy)");
281 static int vnlru_nowhere;
282 SYSCTL_INT(_debug, OID_AUTO, vnlru_nowhere, CTLFLAG_RW,
283 &vnlru_nowhere, 0, "Number of times the vnlru process ran without success");
284
285 /*
286 * Macros to control when a vnode is freed and recycled. All require
287 * the vnode interlock.
288 */
289 #define VCANRECYCLE(vp) (((vp)->v_iflag & VI_FREE) && !(vp)->v_holdcnt)
290 #define VSHOULDFREE(vp) (!((vp)->v_iflag & VI_FREE) && !(vp)->v_holdcnt)
291 #define VSHOULDBUSY(vp) (((vp)->v_iflag & VI_FREE) && (vp)->v_holdcnt)
292
293 /* Shift count for (uintptr_t)vp to initialize vp->v_hash. */
294 static int vnsz2log;
295
296 /*
297 * Initialize the vnode management data structures.
298 *
299 * Reevaluate the following cap on the number of vnodes after the physical
300 * memory size exceeds 512GB. In the limit, as the physical memory size
301 * grows, the ratio of physical pages to vnodes approaches sixteen to one.
302 */
303 #ifndef MAXVNODES_MAX
304 #define MAXVNODES_MAX (512 * (1024 * 1024 * 1024 / (int)PAGE_SIZE / 16))
305 #endif
306 static void
307 vntblinit(void *dummy __unused)
308 {
309 u_int i;
310 int physvnodes, virtvnodes;
311
312 /*
313 * Desiredvnodes is a function of the physical memory size and the
314 * kernel's heap size. Generally speaking, it scales with the
315 * physical memory size. The ratio of desiredvnodes to physical pages
316 * is one to four until desiredvnodes exceeds 98,304. Thereafter, the
317 * marginal ratio of desiredvnodes to physical pages is one to
318 * sixteen. However, desiredvnodes is limited by the kernel's heap
319 * size. The memory required by desiredvnodes vnodes and vm objects
320 * may not exceed one seventh of the kernel's heap size.
321 */
322 physvnodes = maxproc + cnt.v_page_count / 16 + 3 * min(98304 * 4,
323 cnt.v_page_count) / 16;
324 virtvnodes = vm_kmem_size / (7 * (sizeof(struct vm_object) +
325 sizeof(struct vnode)));
326 desiredvnodes = min(physvnodes, virtvnodes);
327 if (desiredvnodes > MAXVNODES_MAX) {
328 if (bootverbose)
329 printf("Reducing kern.maxvnodes %d -> %d\n",
330 desiredvnodes, MAXVNODES_MAX);
331 desiredvnodes = MAXVNODES_MAX;
332 }
333 wantfreevnodes = desiredvnodes / 4;
334 mtx_init(&mntid_mtx, "mntid", NULL, MTX_DEF);
335 TAILQ_INIT(&vnode_free_list);
336 mtx_init(&vnode_free_list_mtx, "vnode_free_list", NULL, MTX_DEF);
337 vnode_zone = uma_zcreate("VNODE", sizeof (struct vnode), NULL, NULL,
338 NULL, NULL, UMA_ALIGN_PTR, 0);
339 vnodepoll_zone = uma_zcreate("VNODEPOLL", sizeof (struct vpollinfo),
340 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0);
341 /*
342 * Initialize the filesystem syncer.
343 */
344 syncer_workitem_pending[WI_MPSAFEQ] = hashinit(syncer_maxdelay, M_VNODE,
345 &syncer_mask);
346 syncer_workitem_pending[WI_GIANTQ] = hashinit(syncer_maxdelay, M_VNODE,
347 &syncer_mask);
348 syncer_maxdelay = syncer_mask + 1;
349 mtx_init(&sync_mtx, "Syncer mtx", NULL, MTX_DEF);
350 cv_init(&sync_wakeup, "syncer");
351 for (i = 1; i <= sizeof(struct vnode); i <<= 1)
352 vnsz2log++;
353 vnsz2log--;
354 }
355 SYSINIT(vfs, SI_SUB_VFS, SI_ORDER_FIRST, vntblinit, NULL);
356
357
358 /*
359 * Mark a mount point as busy. Used to synchronize access and to delay
360 * unmounting. Eventually, mountlist_mtx is not released on failure.
361 *
362 * vfs_busy() is a custom lock, it can block the caller.
363 * vfs_busy() only sleeps if the unmount is active on the mount point.
364 * For a mountpoint mp, vfs_busy-enforced lock is before lock of any
365 * vnode belonging to mp.
366 *
367 * Lookup uses vfs_busy() to traverse mount points.
368 * root fs var fs
369 * / vnode lock A / vnode lock (/var) D
370 * /var vnode lock B /log vnode lock(/var/log) E
371 * vfs_busy lock C vfs_busy lock F
372 *
373 * Within each file system, the lock order is C->A->B and F->D->E.
374 *
375 * When traversing across mounts, the system follows that lock order:
376 *
377 * C->A->B
378 * |
379 * +->F->D->E
380 *
381 * The lookup() process for namei("/var") illustrates the process:
382 * VOP_LOOKUP() obtains B while A is held
383 * vfs_busy() obtains a shared lock on F while A and B are held
384 * vput() releases lock on B
385 * vput() releases lock on A
386 * VFS_ROOT() obtains lock on D while shared lock on F is held
387 * vfs_unbusy() releases shared lock on F
388 * vn_lock() obtains lock on deadfs vnode vp_crossmp instead of A.
389 * Attempt to lock A (instead of vp_crossmp) while D is held would
390 * violate the global order, causing deadlocks.
391 *
392 * dounmount() locks B while F is drained.
393 */
394 int
395 vfs_busy(struct mount *mp, int flags)
396 {
397
398 MPASS((flags & ~MBF_MASK) == 0);
399 CTR3(KTR_VFS, "%s: mp %p with flags %d", __func__, mp, flags);
400
401 MNT_ILOCK(mp);
402 MNT_REF(mp);
403 /*
404 * If mount point is currenly being unmounted, sleep until the
405 * mount point fate is decided. If thread doing the unmounting fails,
406 * it will clear MNTK_UNMOUNT flag before waking us up, indicating
407 * that this mount point has survived the unmount attempt and vfs_busy
408 * should retry. Otherwise the unmounter thread will set MNTK_REFEXPIRE
409 * flag in addition to MNTK_UNMOUNT, indicating that mount point is
410 * about to be really destroyed. vfs_busy needs to release its
411 * reference on the mount point in this case and return with ENOENT,
412 * telling the caller that mount mount it tried to busy is no longer
413 * valid.
414 */
415 while (mp->mnt_kern_flag & MNTK_UNMOUNT) {
416 if (flags & MBF_NOWAIT || mp->mnt_kern_flag & MNTK_REFEXPIRE) {
417 MNT_REL(mp);
418 MNT_IUNLOCK(mp);
419 CTR1(KTR_VFS, "%s: failed busying before sleeping",
420 __func__);
421 return (ENOENT);
422 }
423 if (flags & MBF_MNTLSTLOCK)
424 mtx_unlock(&mountlist_mtx);
425 mp->mnt_kern_flag |= MNTK_MWAIT;
426 msleep(mp, MNT_MTX(mp), PVFS | PDROP, "vfs_busy", 0);
427 if (flags & MBF_MNTLSTLOCK)
428 mtx_lock(&mountlist_mtx);
429 MNT_ILOCK(mp);
430 }
431 if (flags & MBF_MNTLSTLOCK)
432 mtx_unlock(&mountlist_mtx);
433 mp->mnt_lockref++;
434 MNT_IUNLOCK(mp);
435 return (0);
436 }
437
438 /*
439 * Free a busy filesystem.
440 */
441 void
442 vfs_unbusy(struct mount *mp)
443 {
444
445 CTR2(KTR_VFS, "%s: mp %p", __func__, mp);
446 MNT_ILOCK(mp);
447 MNT_REL(mp);
448 KASSERT(mp->mnt_lockref > 0, ("negative mnt_lockref"));
449 mp->mnt_lockref--;
450 if (mp->mnt_lockref == 0 && (mp->mnt_kern_flag & MNTK_DRAINING) != 0) {
451 MPASS(mp->mnt_kern_flag & MNTK_UNMOUNT);
452 CTR1(KTR_VFS, "%s: waking up waiters", __func__);
453 mp->mnt_kern_flag &= ~MNTK_DRAINING;
454 wakeup(&mp->mnt_lockref);
455 }
456 MNT_IUNLOCK(mp);
457 }
458
459 /*
460 * Lookup a mount point by filesystem identifier.
461 */
462 struct mount *
463 vfs_getvfs(fsid_t *fsid)
464 {
465 struct mount *mp;
466
467 CTR2(KTR_VFS, "%s: fsid %p", __func__, fsid);
468 mtx_lock(&mountlist_mtx);
469 TAILQ_FOREACH(mp, &mountlist, mnt_list) {
470 if (mp->mnt_stat.f_fsid.val[0] == fsid->val[0] &&
471 mp->mnt_stat.f_fsid.val[1] == fsid->val[1]) {
472 vfs_ref(mp);
473 mtx_unlock(&mountlist_mtx);
474 return (mp);
475 }
476 }
477 mtx_unlock(&mountlist_mtx);
478 CTR2(KTR_VFS, "%s: lookup failed for %p id", __func__, fsid);
479 return ((struct mount *) 0);
480 }
481
482 /*
483 * Lookup a mount point by filesystem identifier, busying it before
484 * returning.
485 *
486 * To avoid congestion on mountlist_mtx, implement simple direct-mapped
487 * cache for popular filesystem identifiers. The cache is lockess, using
488 * the fact that struct mount's are never freed. In worst case we may
489 * get pointer to unmounted or even different filesystem, so we have to
490 * check what we got, and go slow way if so.
491 */
492 struct mount *
493 vfs_busyfs(fsid_t *fsid)
494 {
495 #define FSID_CACHE_SIZE 256
496 typedef struct mount * volatile vmp_t;
497 static vmp_t cache[FSID_CACHE_SIZE];
498 struct mount *mp;
499 int error;
500 uint32_t hash;
501
502 CTR2(KTR_VFS, "%s: fsid %p", __func__, fsid);
503 hash = fsid->val[0] ^ fsid->val[1];
504 hash = (hash >> 16 ^ hash) & (FSID_CACHE_SIZE - 1);
505 mp = cache[hash];
506 if (mp == NULL ||
507 mp->mnt_stat.f_fsid.val[0] != fsid->val[0] ||
508 mp->mnt_stat.f_fsid.val[1] != fsid->val[1])
509 goto slow;
510 if (vfs_busy(mp, 0) != 0) {
511 cache[hash] = NULL;
512 goto slow;
513 }
514 if (mp->mnt_stat.f_fsid.val[0] == fsid->val[0] &&
515 mp->mnt_stat.f_fsid.val[1] == fsid->val[1])
516 return (mp);
517 else
518 vfs_unbusy(mp);
519
520 slow:
521 mtx_lock(&mountlist_mtx);
522 TAILQ_FOREACH(mp, &mountlist, mnt_list) {
523 if (mp->mnt_stat.f_fsid.val[0] == fsid->val[0] &&
524 mp->mnt_stat.f_fsid.val[1] == fsid->val[1]) {
525 error = vfs_busy(mp, MBF_MNTLSTLOCK);
526 if (error) {
527 cache[hash] = NULL;
528 mtx_unlock(&mountlist_mtx);
529 return (NULL);
530 }
531 cache[hash] = mp;
532 return (mp);
533 }
534 }
535 CTR2(KTR_VFS, "%s: lookup failed for %p id", __func__, fsid);
536 mtx_unlock(&mountlist_mtx);
537 return ((struct mount *) 0);
538 }
539
540 /*
541 * Check if a user can access privileged mount options.
542 */
543 int
544 vfs_suser(struct mount *mp, struct thread *td)
545 {
546 int error;
547
548 /*
549 * If the thread is jailed, but this is not a jail-friendly file
550 * system, deny immediately.
551 */
552 if (!(mp->mnt_vfc->vfc_flags & VFCF_JAIL) && jailed(td->td_ucred))
553 return (EPERM);
554
555 /*
556 * If the file system was mounted outside the jail of the calling
557 * thread, deny immediately.
558 */
559 if (prison_check(td->td_ucred, mp->mnt_cred) != 0)
560 return (EPERM);
561
562 /*
563 * If file system supports delegated administration, we don't check
564 * for the PRIV_VFS_MOUNT_OWNER privilege - it will be better verified
565 * by the file system itself.
566 * If this is not the user that did original mount, we check for
567 * the PRIV_VFS_MOUNT_OWNER privilege.
568 */
569 if (!(mp->mnt_vfc->vfc_flags & VFCF_DELEGADMIN) &&
570 mp->mnt_cred->cr_uid != td->td_ucred->cr_uid) {
571 if ((error = priv_check(td, PRIV_VFS_MOUNT_OWNER)) != 0)
572 return (error);
573 }
574 return (0);
575 }
576
577 /*
578 * Get a new unique fsid. Try to make its val[0] unique, since this value
579 * will be used to create fake device numbers for stat(). Also try (but
580 * not so hard) make its val[0] unique mod 2^16, since some emulators only
581 * support 16-bit device numbers. We end up with unique val[0]'s for the
582 * first 2^16 calls and unique val[0]'s mod 2^16 for the first 2^8 calls.
583 *
584 * Keep in mind that several mounts may be running in parallel. Starting
585 * the search one past where the previous search terminated is both a
586 * micro-optimization and a defense against returning the same fsid to
587 * different mounts.
588 */
589 void
590 vfs_getnewfsid(struct mount *mp)
591 {
592 static uint16_t mntid_base;
593 struct mount *nmp;
594 fsid_t tfsid;
595 int mtype;
596
597 CTR2(KTR_VFS, "%s: mp %p", __func__, mp);
598 mtx_lock(&mntid_mtx);
599 mtype = mp->mnt_vfc->vfc_typenum;
600 tfsid.val[1] = mtype;
601 mtype = (mtype & 0xFF) << 24;
602 for (;;) {
603 tfsid.val[0] = makedev(255,
604 mtype | ((mntid_base & 0xFF00) << 8) | (mntid_base & 0xFF));
605 mntid_base++;
606 if ((nmp = vfs_getvfs(&tfsid)) == NULL)
607 break;
608 vfs_rel(nmp);
609 }
610 mp->mnt_stat.f_fsid.val[0] = tfsid.val[0];
611 mp->mnt_stat.f_fsid.val[1] = tfsid.val[1];
612 mtx_unlock(&mntid_mtx);
613 }
614
615 /*
616 * Knob to control the precision of file timestamps:
617 *
618 * 0 = seconds only; nanoseconds zeroed.
619 * 1 = seconds and nanoseconds, accurate within 1/HZ.
620 * 2 = seconds and nanoseconds, truncated to microseconds.
621 * >=3 = seconds and nanoseconds, maximum precision.
622 */
623 enum { TSP_SEC, TSP_HZ, TSP_USEC, TSP_NSEC };
624
625 static int timestamp_precision = TSP_USEC;
626 SYSCTL_INT(_vfs, OID_AUTO, timestamp_precision, CTLFLAG_RW,
627 ×tamp_precision, 0, "File timestamp precision (0: seconds, "
628 "1: sec + ns accurate to 1/HZ, 2: sec + ns truncated to ms, "
629 "3+: sec + ns (max. precision))");
630
631 /*
632 * Get a current timestamp.
633 */
634 void
635 vfs_timestamp(struct timespec *tsp)
636 {
637 struct timeval tv;
638
639 switch (timestamp_precision) {
640 case TSP_SEC:
641 tsp->tv_sec = time_second;
642 tsp->tv_nsec = 0;
643 break;
644 case TSP_HZ:
645 getnanotime(tsp);
646 break;
647 case TSP_USEC:
648 microtime(&tv);
649 TIMEVAL_TO_TIMESPEC(&tv, tsp);
650 break;
651 case TSP_NSEC:
652 default:
653 nanotime(tsp);
654 break;
655 }
656 }
657
658 /*
659 * Set vnode attributes to VNOVAL
660 */
661 void
662 vattr_null(struct vattr *vap)
663 {
664
665 vap->va_type = VNON;
666 vap->va_size = VNOVAL;
667 vap->va_bytes = VNOVAL;
668 vap->va_mode = VNOVAL;
669 vap->va_nlink = VNOVAL;
670 vap->va_uid = VNOVAL;
671 vap->va_gid = VNOVAL;
672 vap->va_fsid = VNOVAL;
673 vap->va_fileid = VNOVAL;
674 vap->va_blocksize = VNOVAL;
675 vap->va_rdev = VNOVAL;
676 vap->va_atime.tv_sec = VNOVAL;
677 vap->va_atime.tv_nsec = VNOVAL;
678 vap->va_mtime.tv_sec = VNOVAL;
679 vap->va_mtime.tv_nsec = VNOVAL;
680 vap->va_ctime.tv_sec = VNOVAL;
681 vap->va_ctime.tv_nsec = VNOVAL;
682 vap->va_birthtime.tv_sec = VNOVAL;
683 vap->va_birthtime.tv_nsec = VNOVAL;
684 vap->va_flags = VNOVAL;
685 vap->va_gen = VNOVAL;
686 vap->va_vaflags = 0;
687 }
688
689 /*
690 * This routine is called when we have too many vnodes. It attempts
691 * to free <count> vnodes and will potentially free vnodes that still
692 * have VM backing store (VM backing store is typically the cause
693 * of a vnode blowout so we want to do this). Therefore, this operation
694 * is not considered cheap.
695 *
696 * A number of conditions may prevent a vnode from being reclaimed.
697 * the buffer cache may have references on the vnode, a directory
698 * vnode may still have references due to the namei cache representing
699 * underlying files, or the vnode may be in active use. It is not
700 * desireable to reuse such vnodes. These conditions may cause the
701 * number of vnodes to reach some minimum value regardless of what
702 * you set kern.maxvnodes to. Do not set kern.maxvnodes too low.
703 */
704 static int
705 vlrureclaim(struct mount *mp)
706 {
707 struct vnode *vp;
708 int done;
709 int trigger;
710 int usevnodes;
711 int count;
712
713 /*
714 * Calculate the trigger point, don't allow user
715 * screwups to blow us up. This prevents us from
716 * recycling vnodes with lots of resident pages. We
717 * aren't trying to free memory, we are trying to
718 * free vnodes.
719 */
720 usevnodes = desiredvnodes;
721 if (usevnodes <= 0)
722 usevnodes = 1;
723 trigger = cnt.v_page_count * 2 / usevnodes;
724 done = 0;
725 vn_start_write(NULL, &mp, V_WAIT);
726 MNT_ILOCK(mp);
727 count = mp->mnt_nvnodelistsize / 10 + 1;
728 while (count != 0) {
729 vp = TAILQ_FIRST(&mp->mnt_nvnodelist);
730 while (vp != NULL && vp->v_type == VMARKER)
731 vp = TAILQ_NEXT(vp, v_nmntvnodes);
732 if (vp == NULL)
733 break;
734 TAILQ_REMOVE(&mp->mnt_nvnodelist, vp, v_nmntvnodes);
735 TAILQ_INSERT_TAIL(&mp->mnt_nvnodelist, vp, v_nmntvnodes);
736 --count;
737 if (!VI_TRYLOCK(vp))
738 goto next_iter;
739 /*
740 * If it's been deconstructed already, it's still
741 * referenced, or it exceeds the trigger, skip it.
742 */
743 if (vp->v_usecount ||
744 (!vlru_allow_cache_src &&
745 !LIST_EMPTY(&(vp)->v_cache_src)) ||
746 (vp->v_iflag & VI_DOOMED) != 0 || (vp->v_object != NULL &&
747 vp->v_object->resident_page_count > trigger)) {
748 VI_UNLOCK(vp);
749 goto next_iter;
750 }
751 MNT_IUNLOCK(mp);
752 vholdl(vp);
753 if (VOP_LOCK(vp, LK_INTERLOCK|LK_EXCLUSIVE|LK_NOWAIT)) {
754 vdrop(vp);
755 goto next_iter_mntunlocked;
756 }
757 VI_LOCK(vp);
758 /*
759 * v_usecount may have been bumped after VOP_LOCK() dropped
760 * the vnode interlock and before it was locked again.
761 *
762 * It is not necessary to recheck VI_DOOMED because it can
763 * only be set by another thread that holds both the vnode
764 * lock and vnode interlock. If another thread has the
765 * vnode lock before we get to VOP_LOCK() and obtains the
766 * vnode interlock after VOP_LOCK() drops the vnode
767 * interlock, the other thread will be unable to drop the
768 * vnode lock before our VOP_LOCK() call fails.
769 */
770 if (vp->v_usecount ||
771 (!vlru_allow_cache_src &&
772 !LIST_EMPTY(&(vp)->v_cache_src)) ||
773 (vp->v_object != NULL &&
774 vp->v_object->resident_page_count > trigger)) {
775 VOP_UNLOCK(vp, LK_INTERLOCK);
776 goto next_iter_mntunlocked;
777 }
778 KASSERT((vp->v_iflag & VI_DOOMED) == 0,
779 ("VI_DOOMED unexpectedly detected in vlrureclaim()"));
780 atomic_add_long(&recycles_count, 1);
781 vgonel(vp);
782 VOP_UNLOCK(vp, 0);
783 vdropl(vp);
784 done++;
785 next_iter_mntunlocked:
786 if (!should_yield())
787 goto relock_mnt;
788 goto yield;
789 next_iter:
790 if (!should_yield())
791 continue;
792 MNT_IUNLOCK(mp);
793 yield:
794 kern_yield(PRI_UNCHANGED);
795 relock_mnt:
796 MNT_ILOCK(mp);
797 }
798 MNT_IUNLOCK(mp);
799 vn_finished_write(mp);
800 return done;
801 }
802
803 /*
804 * Attempt to keep the free list at wantfreevnodes length.
805 */
806 static void
807 vnlru_free(int count)
808 {
809 struct vnode *vp;
810 int vfslocked;
811
812 mtx_assert(&vnode_free_list_mtx, MA_OWNED);
813 for (; count > 0; count--) {
814 vp = TAILQ_FIRST(&vnode_free_list);
815 /*
816 * The list can be modified while the free_list_mtx
817 * has been dropped and vp could be NULL here.
818 */
819 if (!vp)
820 break;
821 VNASSERT(vp->v_op != NULL, vp,
822 ("vnlru_free: vnode already reclaimed."));
823 KASSERT((vp->v_iflag & VI_FREE) != 0,
824 ("Removing vnode not on freelist"));
825 KASSERT((vp->v_iflag & VI_ACTIVE) == 0,
826 ("Mangling active vnode"));
827 TAILQ_REMOVE(&vnode_free_list, vp, v_actfreelist);
828 /*
829 * Don't recycle if we can't get the interlock.
830 */
831 if (!VI_TRYLOCK(vp)) {
832 TAILQ_INSERT_TAIL(&vnode_free_list, vp, v_actfreelist);
833 continue;
834 }
835 VNASSERT(VCANRECYCLE(vp), vp,
836 ("vp inconsistent on freelist"));
837 freevnodes--;
838 vp->v_iflag &= ~VI_FREE;
839 vholdl(vp);
840 mtx_unlock(&vnode_free_list_mtx);
841 VI_UNLOCK(vp);
842 vfslocked = VFS_LOCK_GIANT(vp->v_mount);
843 vtryrecycle(vp);
844 VFS_UNLOCK_GIANT(vfslocked);
845 /*
846 * If the recycled succeeded this vdrop will actually free
847 * the vnode. If not it will simply place it back on
848 * the free list.
849 */
850 vdrop(vp);
851 mtx_lock(&vnode_free_list_mtx);
852 }
853 }
854 /*
855 * Attempt to recycle vnodes in a context that is always safe to block.
856 * Calling vlrurecycle() from the bowels of filesystem code has some
857 * interesting deadlock problems.
858 */
859 static struct proc *vnlruproc;
860 static int vnlruproc_sig;
861
862 static void
863 vnlru_proc(void)
864 {
865 struct mount *mp, *nmp;
866 int done, vfslocked;
867 struct proc *p = vnlruproc;
868
869 EVENTHANDLER_REGISTER(shutdown_pre_sync, kproc_shutdown, p,
870 SHUTDOWN_PRI_FIRST);
871
872 for (;;) {
873 kproc_suspend_check(p);
874 mtx_lock(&vnode_free_list_mtx);
875 if (freevnodes > wantfreevnodes)
876 vnlru_free(freevnodes - wantfreevnodes);
877 if (numvnodes <= desiredvnodes * 9 / 10) {
878 vnlruproc_sig = 0;
879 wakeup(&vnlruproc_sig);
880 msleep(vnlruproc, &vnode_free_list_mtx,
881 PVFS|PDROP, "vlruwt", hz);
882 continue;
883 }
884 mtx_unlock(&vnode_free_list_mtx);
885 done = 0;
886 mtx_lock(&mountlist_mtx);
887 for (mp = TAILQ_FIRST(&mountlist); mp != NULL; mp = nmp) {
888 if (vfs_busy(mp, MBF_NOWAIT | MBF_MNTLSTLOCK)) {
889 nmp = TAILQ_NEXT(mp, mnt_list);
890 continue;
891 }
892 vfslocked = VFS_LOCK_GIANT(mp);
893 done += vlrureclaim(mp);
894 VFS_UNLOCK_GIANT(vfslocked);
895 mtx_lock(&mountlist_mtx);
896 nmp = TAILQ_NEXT(mp, mnt_list);
897 vfs_unbusy(mp);
898 }
899 mtx_unlock(&mountlist_mtx);
900 if (done == 0) {
901 #if 0
902 /* These messages are temporary debugging aids */
903 if (vnlru_nowhere < 5)
904 printf("vnlru process getting nowhere..\n");
905 else if (vnlru_nowhere == 5)
906 printf("vnlru process messages stopped.\n");
907 #endif
908 vnlru_nowhere++;
909 tsleep(vnlruproc, PPAUSE, "vlrup", hz * 3);
910 } else
911 kern_yield(PRI_UNCHANGED);
912 }
913 }
914
915 static struct kproc_desc vnlru_kp = {
916 "vnlru",
917 vnlru_proc,
918 &vnlruproc
919 };
920 SYSINIT(vnlru, SI_SUB_KTHREAD_UPDATE, SI_ORDER_FIRST, kproc_start,
921 &vnlru_kp);
922
923 /*
924 * Routines having to do with the management of the vnode table.
925 */
926
927 /*
928 * Try to recycle a freed vnode. We abort if anyone picks up a reference
929 * before we actually vgone(). This function must be called with the vnode
930 * held to prevent the vnode from being returned to the free list midway
931 * through vgone().
932 */
933 static int
934 vtryrecycle(struct vnode *vp)
935 {
936 struct mount *vnmp;
937
938 CTR2(KTR_VFS, "%s: vp %p", __func__, vp);
939 VNASSERT(vp->v_holdcnt, vp,
940 ("vtryrecycle: Recycling vp %p without a reference.", vp));
941 /*
942 * This vnode may found and locked via some other list, if so we
943 * can't recycle it yet.
944 */
945 if (VOP_LOCK(vp, LK_EXCLUSIVE | LK_NOWAIT) != 0) {
946 CTR2(KTR_VFS,
947 "%s: impossible to recycle, vp %p lock is already held",
948 __func__, vp);
949 return (EWOULDBLOCK);
950 }
951 /*
952 * Don't recycle if its filesystem is being suspended.
953 */
954 if (vn_start_write(vp, &vnmp, V_NOWAIT) != 0) {
955 VOP_UNLOCK(vp, 0);
956 CTR2(KTR_VFS,
957 "%s: impossible to recycle, cannot start the write for %p",
958 __func__, vp);
959 return (EBUSY);
960 }
961 /*
962 * If we got this far, we need to acquire the interlock and see if
963 * anyone picked up this vnode from another list. If not, we will
964 * mark it with DOOMED via vgonel() so that anyone who does find it
965 * will skip over it.
966 */
967 VI_LOCK(vp);
968 if (vp->v_usecount) {
969 VOP_UNLOCK(vp, LK_INTERLOCK);
970 vn_finished_write(vnmp);
971 CTR2(KTR_VFS,
972 "%s: impossible to recycle, %p is already referenced",
973 __func__, vp);
974 return (EBUSY);
975 }
976 if ((vp->v_iflag & VI_DOOMED) == 0) {
977 atomic_add_long(&recycles_count, 1);
978 vgonel(vp);
979 }
980 VOP_UNLOCK(vp, LK_INTERLOCK);
981 vn_finished_write(vnmp);
982 return (0);
983 }
984
985 /*
986 * Wait for available vnodes.
987 */
988 static int
989 getnewvnode_wait(int suspended)
990 {
991
992 mtx_assert(&vnode_free_list_mtx, MA_OWNED);
993 if (numvnodes > desiredvnodes) {
994 if (suspended) {
995 /*
996 * File system is beeing suspended, we cannot risk a
997 * deadlock here, so allocate new vnode anyway.
998 */
999 if (freevnodes > wantfreevnodes)
1000 vnlru_free(freevnodes - wantfreevnodes);
1001 return (0);
1002 }
1003 if (vnlruproc_sig == 0) {
1004 vnlruproc_sig = 1; /* avoid unnecessary wakeups */
1005 wakeup(vnlruproc);
1006 }
1007 msleep(&vnlruproc_sig, &vnode_free_list_mtx, PVFS,
1008 "vlruwk", hz);
1009 }
1010 return (numvnodes > desiredvnodes ? ENFILE : 0);
1011 }
1012
1013 void
1014 getnewvnode_reserve(u_int count)
1015 {
1016 struct thread *td;
1017
1018 td = curthread;
1019 /* First try to be quick and racy. */
1020 if (atomic_fetchadd_long(&numvnodes, count) + count <= desiredvnodes) {
1021 td->td_vp_reserv += count;
1022 return;
1023 } else
1024 atomic_subtract_long(&numvnodes, count);
1025
1026 mtx_lock(&vnode_free_list_mtx);
1027 while (count > 0) {
1028 if (getnewvnode_wait(0) == 0) {
1029 count--;
1030 td->td_vp_reserv++;
1031 atomic_add_long(&numvnodes, 1);
1032 }
1033 }
1034 mtx_unlock(&vnode_free_list_mtx);
1035 }
1036
1037 void
1038 getnewvnode_drop_reserve(void)
1039 {
1040 struct thread *td;
1041
1042 td = curthread;
1043 atomic_subtract_long(&numvnodes, td->td_vp_reserv);
1044 td->td_vp_reserv = 0;
1045 }
1046
1047 /*
1048 * Return the next vnode from the free list.
1049 */
1050 int
1051 getnewvnode(const char *tag, struct mount *mp, struct vop_vector *vops,
1052 struct vnode **vpp)
1053 {
1054 struct vnode *vp;
1055 struct bufobj *bo;
1056 struct thread *td;
1057 int error;
1058
1059 CTR3(KTR_VFS, "%s: mp %p with tag %s", __func__, mp, tag);
1060 vp = NULL;
1061 td = curthread;
1062 if (td->td_vp_reserv > 0) {
1063 td->td_vp_reserv -= 1;
1064 goto alloc;
1065 }
1066 mtx_lock(&vnode_free_list_mtx);
1067 /*
1068 * Lend our context to reclaim vnodes if they've exceeded the max.
1069 */
1070 if (freevnodes > wantfreevnodes)
1071 vnlru_free(1);
1072 error = getnewvnode_wait(mp != NULL && (mp->mnt_kern_flag &
1073 MNTK_SUSPEND));
1074 #if 0 /* XXX Not all VFS_VGET/ffs_vget callers check returns. */
1075 if (error != 0) {
1076 mtx_unlock(&vnode_free_list_mtx);
1077 return (error);
1078 }
1079 #endif
1080 atomic_add_long(&numvnodes, 1);
1081 mtx_unlock(&vnode_free_list_mtx);
1082 alloc:
1083 atomic_add_long(&vnodes_created, 1);
1084 vp = (struct vnode *) uma_zalloc(vnode_zone, M_WAITOK|M_ZERO);
1085 /*
1086 * Setup locks.
1087 */
1088 vp->v_vnlock = &vp->v_lock;
1089 mtx_init(&vp->v_interlock, "vnode interlock", NULL, MTX_DEF);
1090 /*
1091 * By default, don't allow shared locks unless filesystems
1092 * opt-in.
1093 */
1094 lockinit(vp->v_vnlock, PVFS, tag, VLKTIMEOUT, LK_NOSHARE);
1095 /*
1096 * Initialize bufobj.
1097 */
1098 bo = &vp->v_bufobj;
1099 bo->__bo_vnode = vp;
1100 mtx_init(BO_MTX(bo), "bufobj interlock", NULL, MTX_DEF);
1101 bo->bo_ops = &buf_ops_bio;
1102 bo->bo_private = vp;
1103 TAILQ_INIT(&bo->bo_clean.bv_hd);
1104 TAILQ_INIT(&bo->bo_dirty.bv_hd);
1105 /*
1106 * Initialize namecache.
1107 */
1108 LIST_INIT(&vp->v_cache_src);
1109 TAILQ_INIT(&vp->v_cache_dst);
1110 /*
1111 * Finalize various vnode identity bits.
1112 */
1113 vp->v_type = VNON;
1114 vp->v_tag = tag;
1115 vp->v_op = vops;
1116 v_incr_usecount(vp);
1117 vp->v_data = 0;
1118 #ifdef MAC
1119 mac_vnode_init(vp);
1120 if (mp != NULL && (mp->mnt_flag & MNT_MULTILABEL) == 0)
1121 mac_vnode_associate_singlelabel(mp, vp);
1122 else if (mp == NULL && vops != &dead_vnodeops)
1123 printf("NULL mp in getnewvnode()\n");
1124 #endif
1125 if (mp != NULL) {
1126 bo->bo_bsize = mp->mnt_stat.f_iosize;
1127 if ((mp->mnt_kern_flag & MNTK_NOKNOTE) != 0)
1128 vp->v_vflag |= VV_NOKNOTE;
1129 }
1130 rangelock_init(&vp->v_rl);
1131
1132 /*
1133 * For the filesystems which do not use vfs_hash_insert(),
1134 * still initialize v_hash to have vfs_hash_index() useful.
1135 * E.g., nullfs uses vfs_hash_index() on the lower vnode for
1136 * its own hashing.
1137 */
1138 vp->v_hash = (uintptr_t)vp >> vnsz2log;
1139
1140 *vpp = vp;
1141 return (0);
1142 }
1143
1144 /*
1145 * Delete from old mount point vnode list, if on one.
1146 */
1147 static void
1148 delmntque(struct vnode *vp)
1149 {
1150 struct mount *mp;
1151 int active;
1152
1153 mp = vp->v_mount;
1154 if (mp == NULL)
1155 return;
1156 MNT_ILOCK(mp);
1157 VI_LOCK(vp);
1158 KASSERT(mp->mnt_activevnodelistsize <= mp->mnt_nvnodelistsize,
1159 ("Active vnode list size %d > Vnode list size %d",
1160 mp->mnt_activevnodelistsize, mp->mnt_nvnodelistsize));
1161 active = vp->v_iflag & VI_ACTIVE;
1162 vp->v_iflag &= ~VI_ACTIVE;
1163 if (active) {
1164 mtx_lock(&vnode_free_list_mtx);
1165 TAILQ_REMOVE(&mp->mnt_activevnodelist, vp, v_actfreelist);
1166 mp->mnt_activevnodelistsize--;
1167 mtx_unlock(&vnode_free_list_mtx);
1168 }
1169 vp->v_mount = NULL;
1170 VI_UNLOCK(vp);
1171 VNASSERT(mp->mnt_nvnodelistsize > 0, vp,
1172 ("bad mount point vnode list size"));
1173 TAILQ_REMOVE(&mp->mnt_nvnodelist, vp, v_nmntvnodes);
1174 mp->mnt_nvnodelistsize--;
1175 MNT_REL(mp);
1176 MNT_IUNLOCK(mp);
1177 }
1178
1179 static void
1180 insmntque_stddtr(struct vnode *vp, void *dtr_arg)
1181 {
1182
1183 vp->v_data = NULL;
1184 vp->v_op = &dead_vnodeops;
1185 /* XXX non mp-safe fs may still call insmntque with vnode
1186 unlocked */
1187 if (!VOP_ISLOCKED(vp))
1188 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
1189 vgone(vp);
1190 vput(vp);
1191 }
1192
1193 /*
1194 * Insert into list of vnodes for the new mount point, if available.
1195 */
1196 int
1197 insmntque1(struct vnode *vp, struct mount *mp,
1198 void (*dtr)(struct vnode *, void *), void *dtr_arg)
1199 {
1200 int locked;
1201
1202 KASSERT(vp->v_mount == NULL,
1203 ("insmntque: vnode already on per mount vnode list"));
1204 VNASSERT(mp != NULL, vp, ("Don't call insmntque(foo, NULL)"));
1205 #ifdef DEBUG_VFS_LOCKS
1206 if (!VFS_NEEDSGIANT(mp))
1207 ASSERT_VOP_ELOCKED(vp,
1208 "insmntque: mp-safe fs and non-locked vp");
1209 #endif
1210 /*
1211 * We acquire the vnode interlock early to ensure that the
1212 * vnode cannot be recycled by another process releasing a
1213 * holdcnt on it before we get it on both the vnode list
1214 * and the active vnode list. The mount mutex protects only
1215 * manipulation of the vnode list and the vnode freelist
1216 * mutex protects only manipulation of the active vnode list.
1217 * Hence the need to hold the vnode interlock throughout.
1218 */
1219 MNT_ILOCK(mp);
1220 VI_LOCK(vp);
1221 if ((mp->mnt_kern_flag & MNTK_NOINSMNTQ) != 0 &&
1222 ((mp->mnt_kern_flag & MNTK_UNMOUNTF) != 0 ||
1223 mp->mnt_nvnodelistsize == 0)) {
1224 locked = VOP_ISLOCKED(vp);
1225 if (!locked || (locked == LK_EXCLUSIVE &&
1226 (vp->v_vflag & VV_FORCEINSMQ) == 0)) {
1227 VI_UNLOCK(vp);
1228 MNT_IUNLOCK(mp);
1229 if (dtr != NULL)
1230 dtr(vp, dtr_arg);
1231 return (EBUSY);
1232 }
1233 }
1234 vp->v_mount = mp;
1235 MNT_REF(mp);
1236 TAILQ_INSERT_TAIL(&mp->mnt_nvnodelist, vp, v_nmntvnodes);
1237 VNASSERT(mp->mnt_nvnodelistsize >= 0, vp,
1238 ("neg mount point vnode list size"));
1239 mp->mnt_nvnodelistsize++;
1240 KASSERT((vp->v_iflag & VI_ACTIVE) == 0,
1241 ("Activating already active vnode"));
1242 vp->v_iflag |= VI_ACTIVE;
1243 mtx_lock(&vnode_free_list_mtx);
1244 TAILQ_INSERT_HEAD(&mp->mnt_activevnodelist, vp, v_actfreelist);
1245 mp->mnt_activevnodelistsize++;
1246 mtx_unlock(&vnode_free_list_mtx);
1247 VI_UNLOCK(vp);
1248 MNT_IUNLOCK(mp);
1249 return (0);
1250 }
1251
1252 int
1253 insmntque(struct vnode *vp, struct mount *mp)
1254 {
1255
1256 return (insmntque1(vp, mp, insmntque_stddtr, NULL));
1257 }
1258
1259 /*
1260 * Flush out and invalidate all buffers associated with a bufobj
1261 * Called with the underlying object locked.
1262 */
1263 int
1264 bufobj_invalbuf(struct bufobj *bo, int flags, int slpflag, int slptimeo)
1265 {
1266 int error;
1267
1268 BO_LOCK(bo);
1269 if (flags & V_SAVE) {
1270 error = bufobj_wwait(bo, slpflag, slptimeo);
1271 if (error) {
1272 BO_UNLOCK(bo);
1273 return (error);
1274 }
1275 if (bo->bo_dirty.bv_cnt > 0) {
1276 BO_UNLOCK(bo);
1277 if ((error = BO_SYNC(bo, MNT_WAIT)) != 0)
1278 return (error);
1279 /*
1280 * XXX We could save a lock/unlock if this was only
1281 * enabled under INVARIANTS
1282 */
1283 BO_LOCK(bo);
1284 if (bo->bo_numoutput > 0 || bo->bo_dirty.bv_cnt > 0)
1285 panic("vinvalbuf: dirty bufs");
1286 }
1287 }
1288 /*
1289 * If you alter this loop please notice that interlock is dropped and
1290 * reacquired in flushbuflist. Special care is needed to ensure that
1291 * no race conditions occur from this.
1292 */
1293 do {
1294 error = flushbuflist(&bo->bo_clean,
1295 flags, bo, slpflag, slptimeo);
1296 if (error == 0 && !(flags & V_CLEANONLY))
1297 error = flushbuflist(&bo->bo_dirty,
1298 flags, bo, slpflag, slptimeo);
1299 if (error != 0 && error != EAGAIN) {
1300 BO_UNLOCK(bo);
1301 return (error);
1302 }
1303 } while (error != 0);
1304
1305 /*
1306 * Wait for I/O to complete. XXX needs cleaning up. The vnode can
1307 * have write I/O in-progress but if there is a VM object then the
1308 * VM object can also have read-I/O in-progress.
1309 */
1310 do {
1311 bufobj_wwait(bo, 0, 0);
1312 BO_UNLOCK(bo);
1313 if (bo->bo_object != NULL) {
1314 VM_OBJECT_LOCK(bo->bo_object);
1315 vm_object_pip_wait(bo->bo_object, "bovlbx");
1316 VM_OBJECT_UNLOCK(bo->bo_object);
1317 }
1318 BO_LOCK(bo);
1319 } while (bo->bo_numoutput > 0);
1320 BO_UNLOCK(bo);
1321
1322 /*
1323 * Destroy the copy in the VM cache, too.
1324 */
1325 if (bo->bo_object != NULL &&
1326 (flags & (V_ALT | V_NORMAL | V_CLEANONLY)) == 0) {
1327 VM_OBJECT_LOCK(bo->bo_object);
1328 vm_object_page_remove(bo->bo_object, 0, 0, (flags & V_SAVE) ?
1329 OBJPR_CLEANONLY : 0);
1330 VM_OBJECT_UNLOCK(bo->bo_object);
1331 }
1332
1333 #ifdef INVARIANTS
1334 BO_LOCK(bo);
1335 if ((flags & (V_ALT | V_NORMAL | V_CLEANONLY)) == 0 &&
1336 (bo->bo_dirty.bv_cnt > 0 || bo->bo_clean.bv_cnt > 0))
1337 panic("vinvalbuf: flush failed");
1338 BO_UNLOCK(bo);
1339 #endif
1340 return (0);
1341 }
1342
1343 /*
1344 * Flush out and invalidate all buffers associated with a vnode.
1345 * Called with the underlying object locked.
1346 */
1347 int
1348 vinvalbuf(struct vnode *vp, int flags, int slpflag, int slptimeo)
1349 {
1350
1351 CTR3(KTR_VFS, "%s: vp %p with flags %d", __func__, vp, flags);
1352 ASSERT_VOP_LOCKED(vp, "vinvalbuf");
1353 if (vp->v_object != NULL && vp->v_object->handle != vp)
1354 return (0);
1355 return (bufobj_invalbuf(&vp->v_bufobj, flags, slpflag, slptimeo));
1356 }
1357
1358 /*
1359 * Flush out buffers on the specified list.
1360 *
1361 */
1362 static int
1363 flushbuflist( struct bufv *bufv, int flags, struct bufobj *bo, int slpflag,
1364 int slptimeo)
1365 {
1366 struct buf *bp, *nbp;
1367 int retval, error;
1368 daddr_t lblkno;
1369 b_xflags_t xflags;
1370
1371 ASSERT_BO_LOCKED(bo);
1372
1373 retval = 0;
1374 TAILQ_FOREACH_SAFE(bp, &bufv->bv_hd, b_bobufs, nbp) {
1375 if (((flags & V_NORMAL) && (bp->b_xflags & BX_ALTDATA)) ||
1376 ((flags & V_ALT) && (bp->b_xflags & BX_ALTDATA) == 0)) {
1377 continue;
1378 }
1379 lblkno = 0;
1380 xflags = 0;
1381 if (nbp != NULL) {
1382 lblkno = nbp->b_lblkno;
1383 xflags = nbp->b_xflags &
1384 (BX_BKGRDMARKER | BX_VNDIRTY | BX_VNCLEAN);
1385 }
1386 retval = EAGAIN;
1387 error = BUF_TIMELOCK(bp,
1388 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK, BO_MTX(bo),
1389 "flushbuf", slpflag, slptimeo);
1390 if (error) {
1391 BO_LOCK(bo);
1392 return (error != ENOLCK ? error : EAGAIN);
1393 }
1394 KASSERT(bp->b_bufobj == bo,
1395 ("bp %p wrong b_bufobj %p should be %p",
1396 bp, bp->b_bufobj, bo));
1397 if (bp->b_bufobj != bo) { /* XXX: necessary ? */
1398 BUF_UNLOCK(bp);
1399 BO_LOCK(bo);
1400 return (EAGAIN);
1401 }
1402 /*
1403 * XXX Since there are no node locks for NFS, I
1404 * believe there is a slight chance that a delayed
1405 * write will occur while sleeping just above, so
1406 * check for it.
1407 */
1408 if (((bp->b_flags & (B_DELWRI | B_INVAL)) == B_DELWRI) &&
1409 (flags & V_SAVE)) {
1410 BO_LOCK(bo);
1411 bremfree(bp);
1412 BO_UNLOCK(bo);
1413 bp->b_flags |= B_ASYNC;
1414 bwrite(bp);
1415 BO_LOCK(bo);
1416 return (EAGAIN); /* XXX: why not loop ? */
1417 }
1418 BO_LOCK(bo);
1419 bremfree(bp);
1420 BO_UNLOCK(bo);
1421 bp->b_flags |= (B_INVAL | B_RELBUF);
1422 bp->b_flags &= ~B_ASYNC;
1423 brelse(bp);
1424 BO_LOCK(bo);
1425 if (nbp != NULL &&
1426 (nbp->b_bufobj != bo ||
1427 nbp->b_lblkno != lblkno ||
1428 (nbp->b_xflags &
1429 (BX_BKGRDMARKER | BX_VNDIRTY | BX_VNCLEAN)) != xflags))
1430 break; /* nbp invalid */
1431 }
1432 return (retval);
1433 }
1434
1435 /*
1436 * Truncate a file's buffer and pages to a specified length. This
1437 * is in lieu of the old vinvalbuf mechanism, which performed unneeded
1438 * sync activity.
1439 */
1440 int
1441 vtruncbuf(struct vnode *vp, struct ucred *cred, struct thread *td,
1442 off_t length, int blksize)
1443 {
1444 struct buf *bp, *nbp;
1445 int anyfreed;
1446 int trunclbn;
1447 struct bufobj *bo;
1448
1449 CTR5(KTR_VFS, "%s: vp %p with cred %p and block %d:%ju", __func__,
1450 vp, cred, blksize, (uintmax_t)length);
1451
1452 /*
1453 * Round up to the *next* lbn.
1454 */
1455 trunclbn = (length + blksize - 1) / blksize;
1456
1457 ASSERT_VOP_LOCKED(vp, "vtruncbuf");
1458 restart:
1459 bo = &vp->v_bufobj;
1460 BO_LOCK(bo);
1461 anyfreed = 1;
1462 for (;anyfreed;) {
1463 anyfreed = 0;
1464 TAILQ_FOREACH_SAFE(bp, &bo->bo_clean.bv_hd, b_bobufs, nbp) {
1465 if (bp->b_lblkno < trunclbn)
1466 continue;
1467 if (BUF_LOCK(bp,
1468 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK,
1469 BO_MTX(bo)) == ENOLCK)
1470 goto restart;
1471
1472 BO_LOCK(bo);
1473 bremfree(bp);
1474 BO_UNLOCK(bo);
1475 bp->b_flags |= (B_INVAL | B_RELBUF);
1476 bp->b_flags &= ~B_ASYNC;
1477 brelse(bp);
1478 anyfreed = 1;
1479
1480 BO_LOCK(bo);
1481 if (nbp != NULL &&
1482 (((nbp->b_xflags & BX_VNCLEAN) == 0) ||
1483 (nbp->b_vp != vp) ||
1484 (nbp->b_flags & B_DELWRI))) {
1485 BO_UNLOCK(bo);
1486 goto restart;
1487 }
1488 }
1489
1490 TAILQ_FOREACH_SAFE(bp, &bo->bo_dirty.bv_hd, b_bobufs, nbp) {
1491 if (bp->b_lblkno < trunclbn)
1492 continue;
1493 if (BUF_LOCK(bp,
1494 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK,
1495 BO_MTX(bo)) == ENOLCK)
1496 goto restart;
1497 BO_LOCK(bo);
1498 bremfree(bp);
1499 BO_UNLOCK(bo);
1500 bp->b_flags |= (B_INVAL | B_RELBUF);
1501 bp->b_flags &= ~B_ASYNC;
1502 brelse(bp);
1503 anyfreed = 1;
1504
1505 BO_LOCK(bo);
1506 if (nbp != NULL &&
1507 (((nbp->b_xflags & BX_VNDIRTY) == 0) ||
1508 (nbp->b_vp != vp) ||
1509 (nbp->b_flags & B_DELWRI) == 0)) {
1510 BO_UNLOCK(bo);
1511 goto restart;
1512 }
1513 }
1514 }
1515
1516 if (length > 0) {
1517 restartsync:
1518 TAILQ_FOREACH_SAFE(bp, &bo->bo_dirty.bv_hd, b_bobufs, nbp) {
1519 if (bp->b_lblkno > 0)
1520 continue;
1521 /*
1522 * Since we hold the vnode lock this should only
1523 * fail if we're racing with the buf daemon.
1524 */
1525 if (BUF_LOCK(bp,
1526 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK,
1527 BO_MTX(bo)) == ENOLCK) {
1528 goto restart;
1529 }
1530 VNASSERT((bp->b_flags & B_DELWRI), vp,
1531 ("buf(%p) on dirty queue without DELWRI", bp));
1532
1533 BO_LOCK(bo);
1534 bremfree(bp);
1535 BO_UNLOCK(bo);
1536 bawrite(bp);
1537 BO_LOCK(bo);
1538 goto restartsync;
1539 }
1540 }
1541
1542 bufobj_wwait(bo, 0, 0);
1543 BO_UNLOCK(bo);
1544 vnode_pager_setsize(vp, length);
1545
1546 return (0);
1547 }
1548
1549 /*
1550 * buf_splay() - splay tree core for the clean/dirty list of buffers in
1551 * a vnode.
1552 *
1553 * NOTE: We have to deal with the special case of a background bitmap
1554 * buffer, a situation where two buffers will have the same logical
1555 * block offset. We want (1) only the foreground buffer to be accessed
1556 * in a lookup and (2) must differentiate between the foreground and
1557 * background buffer in the splay tree algorithm because the splay
1558 * tree cannot normally handle multiple entities with the same 'index'.
1559 * We accomplish this by adding differentiating flags to the splay tree's
1560 * numerical domain.
1561 */
1562 static
1563 struct buf *
1564 buf_splay(daddr_t lblkno, b_xflags_t xflags, struct buf *root)
1565 {
1566 struct buf dummy;
1567 struct buf *lefttreemax, *righttreemin, *y;
1568
1569 if (root == NULL)
1570 return (NULL);
1571 lefttreemax = righttreemin = &dummy;
1572 for (;;) {
1573 if (lblkno < root->b_lblkno ||
1574 (lblkno == root->b_lblkno &&
1575 (xflags & BX_BKGRDMARKER) < (root->b_xflags & BX_BKGRDMARKER))) {
1576 if ((y = root->b_left) == NULL)
1577 break;
1578 if (lblkno < y->b_lblkno) {
1579 /* Rotate right. */
1580 root->b_left = y->b_right;
1581 y->b_right = root;
1582 root = y;
1583 if ((y = root->b_left) == NULL)
1584 break;
1585 }
1586 /* Link into the new root's right tree. */
1587 righttreemin->b_left = root;
1588 righttreemin = root;
1589 } else if (lblkno > root->b_lblkno ||
1590 (lblkno == root->b_lblkno &&
1591 (xflags & BX_BKGRDMARKER) > (root->b_xflags & BX_BKGRDMARKER))) {
1592 if ((y = root->b_right) == NULL)
1593 break;
1594 if (lblkno > y->b_lblkno) {
1595 /* Rotate left. */
1596 root->b_right = y->b_left;
1597 y->b_left = root;
1598 root = y;
1599 if ((y = root->b_right) == NULL)
1600 break;
1601 }
1602 /* Link into the new root's left tree. */
1603 lefttreemax->b_right = root;
1604 lefttreemax = root;
1605 } else {
1606 break;
1607 }
1608 root = y;
1609 }
1610 /* Assemble the new root. */
1611 lefttreemax->b_right = root->b_left;
1612 righttreemin->b_left = root->b_right;
1613 root->b_left = dummy.b_right;
1614 root->b_right = dummy.b_left;
1615 return (root);
1616 }
1617
1618 static void
1619 buf_vlist_remove(struct buf *bp)
1620 {
1621 struct buf *root;
1622 struct bufv *bv;
1623
1624 KASSERT(bp->b_bufobj != NULL, ("No b_bufobj %p", bp));
1625 ASSERT_BO_LOCKED(bp->b_bufobj);
1626 KASSERT((bp->b_xflags & (BX_VNDIRTY|BX_VNCLEAN)) !=
1627 (BX_VNDIRTY|BX_VNCLEAN),
1628 ("buf_vlist_remove: Buf %p is on two lists", bp));
1629 if (bp->b_xflags & BX_VNDIRTY)
1630 bv = &bp->b_bufobj->bo_dirty;
1631 else
1632 bv = &bp->b_bufobj->bo_clean;
1633 if (bp != bv->bv_root) {
1634 root = buf_splay(bp->b_lblkno, bp->b_xflags, bv->bv_root);
1635 KASSERT(root == bp, ("splay lookup failed in remove"));
1636 }
1637 if (bp->b_left == NULL) {
1638 root = bp->b_right;
1639 } else {
1640 root = buf_splay(bp->b_lblkno, bp->b_xflags, bp->b_left);
1641 root->b_right = bp->b_right;
1642 }
1643 bv->bv_root = root;
1644 TAILQ_REMOVE(&bv->bv_hd, bp, b_bobufs);
1645 bv->bv_cnt--;
1646 bp->b_xflags &= ~(BX_VNDIRTY | BX_VNCLEAN);
1647 }
1648
1649 /*
1650 * Add the buffer to the sorted clean or dirty block list using a
1651 * splay tree algorithm.
1652 *
1653 * NOTE: xflags is passed as a constant, optimizing this inline function!
1654 */
1655 static void
1656 buf_vlist_add(struct buf *bp, struct bufobj *bo, b_xflags_t xflags)
1657 {
1658 struct buf *root;
1659 struct bufv *bv;
1660
1661 ASSERT_BO_LOCKED(bo);
1662 KASSERT((bp->b_xflags & (BX_VNDIRTY|BX_VNCLEAN)) == 0,
1663 ("buf_vlist_add: Buf %p has existing xflags %d", bp, bp->b_xflags));
1664 bp->b_xflags |= xflags;
1665 if (xflags & BX_VNDIRTY)
1666 bv = &bo->bo_dirty;
1667 else
1668 bv = &bo->bo_clean;
1669
1670 root = buf_splay(bp->b_lblkno, bp->b_xflags, bv->bv_root);
1671 if (root == NULL) {
1672 bp->b_left = NULL;
1673 bp->b_right = NULL;
1674 TAILQ_INSERT_TAIL(&bv->bv_hd, bp, b_bobufs);
1675 } else if (bp->b_lblkno < root->b_lblkno ||
1676 (bp->b_lblkno == root->b_lblkno &&
1677 (bp->b_xflags & BX_BKGRDMARKER) < (root->b_xflags & BX_BKGRDMARKER))) {
1678 bp->b_left = root->b_left;
1679 bp->b_right = root;
1680 root->b_left = NULL;
1681 TAILQ_INSERT_BEFORE(root, bp, b_bobufs);
1682 } else {
1683 bp->b_right = root->b_right;
1684 bp->b_left = root;
1685 root->b_right = NULL;
1686 TAILQ_INSERT_AFTER(&bv->bv_hd, root, bp, b_bobufs);
1687 }
1688 bv->bv_cnt++;
1689 bv->bv_root = bp;
1690 }
1691
1692 /*
1693 * Lookup a buffer using the splay tree. Note that we specifically avoid
1694 * shadow buffers used in background bitmap writes.
1695 *
1696 * This code isn't quite efficient as it could be because we are maintaining
1697 * two sorted lists and do not know which list the block resides in.
1698 *
1699 * During a "make buildworld" the desired buffer is found at one of
1700 * the roots more than 60% of the time. Thus, checking both roots
1701 * before performing either splay eliminates unnecessary splays on the
1702 * first tree splayed.
1703 */
1704 struct buf *
1705 gbincore(struct bufobj *bo, daddr_t lblkno)
1706 {
1707 struct buf *bp;
1708
1709 ASSERT_BO_LOCKED(bo);
1710 if ((bp = bo->bo_clean.bv_root) != NULL &&
1711 bp->b_lblkno == lblkno && !(bp->b_xflags & BX_BKGRDMARKER))
1712 return (bp);
1713 if ((bp = bo->bo_dirty.bv_root) != NULL &&
1714 bp->b_lblkno == lblkno && !(bp->b_xflags & BX_BKGRDMARKER))
1715 return (bp);
1716 if ((bp = bo->bo_clean.bv_root) != NULL) {
1717 bo->bo_clean.bv_root = bp = buf_splay(lblkno, 0, bp);
1718 if (bp->b_lblkno == lblkno && !(bp->b_xflags & BX_BKGRDMARKER))
1719 return (bp);
1720 }
1721 if ((bp = bo->bo_dirty.bv_root) != NULL) {
1722 bo->bo_dirty.bv_root = bp = buf_splay(lblkno, 0, bp);
1723 if (bp->b_lblkno == lblkno && !(bp->b_xflags & BX_BKGRDMARKER))
1724 return (bp);
1725 }
1726 return (NULL);
1727 }
1728
1729 /*
1730 * Associate a buffer with a vnode.
1731 */
1732 void
1733 bgetvp(struct vnode *vp, struct buf *bp)
1734 {
1735 struct bufobj *bo;
1736
1737 bo = &vp->v_bufobj;
1738 ASSERT_BO_LOCKED(bo);
1739 VNASSERT(bp->b_vp == NULL, bp->b_vp, ("bgetvp: not free"));
1740
1741 CTR3(KTR_BUF, "bgetvp(%p) vp %p flags %X", bp, vp, bp->b_flags);
1742 VNASSERT((bp->b_xflags & (BX_VNDIRTY|BX_VNCLEAN)) == 0, vp,
1743 ("bgetvp: bp already attached! %p", bp));
1744
1745 vhold(vp);
1746 if (VFS_NEEDSGIANT(vp->v_mount) || bo->bo_flag & BO_NEEDSGIANT)
1747 bp->b_flags |= B_NEEDSGIANT;
1748 bp->b_vp = vp;
1749 bp->b_bufobj = bo;
1750 /*
1751 * Insert onto list for new vnode.
1752 */
1753 buf_vlist_add(bp, bo, BX_VNCLEAN);
1754 }
1755
1756 /*
1757 * Disassociate a buffer from a vnode.
1758 */
1759 void
1760 brelvp(struct buf *bp)
1761 {
1762 struct bufobj *bo;
1763 struct vnode *vp;
1764
1765 CTR3(KTR_BUF, "brelvp(%p) vp %p flags %X", bp, bp->b_vp, bp->b_flags);
1766 KASSERT(bp->b_vp != NULL, ("brelvp: NULL"));
1767
1768 /*
1769 * Delete from old vnode list, if on one.
1770 */
1771 vp = bp->b_vp; /* XXX */
1772 bo = bp->b_bufobj;
1773 BO_LOCK(bo);
1774 if (bp->b_xflags & (BX_VNDIRTY | BX_VNCLEAN))
1775 buf_vlist_remove(bp);
1776 else
1777 panic("brelvp: Buffer %p not on queue.", bp);
1778 if ((bo->bo_flag & BO_ONWORKLST) && bo->bo_dirty.bv_cnt == 0) {
1779 bo->bo_flag &= ~BO_ONWORKLST;
1780 mtx_lock(&sync_mtx);
1781 LIST_REMOVE(bo, bo_synclist);
1782 syncer_worklist_len--;
1783 mtx_unlock(&sync_mtx);
1784 }
1785 bp->b_flags &= ~B_NEEDSGIANT;
1786 bp->b_vp = NULL;
1787 bp->b_bufobj = NULL;
1788 BO_UNLOCK(bo);
1789 vdrop(vp);
1790 }
1791
1792 /*
1793 * Add an item to the syncer work queue.
1794 */
1795 static void
1796 vn_syncer_add_to_worklist(struct bufobj *bo, int delay)
1797 {
1798 int queue, slot;
1799
1800 ASSERT_BO_LOCKED(bo);
1801
1802 mtx_lock(&sync_mtx);
1803 if (bo->bo_flag & BO_ONWORKLST)
1804 LIST_REMOVE(bo, bo_synclist);
1805 else {
1806 bo->bo_flag |= BO_ONWORKLST;
1807 syncer_worklist_len++;
1808 }
1809
1810 if (delay > syncer_maxdelay - 2)
1811 delay = syncer_maxdelay - 2;
1812 slot = (syncer_delayno + delay) & syncer_mask;
1813
1814 queue = VFS_NEEDSGIANT(bo->__bo_vnode->v_mount) ? WI_GIANTQ :
1815 WI_MPSAFEQ;
1816 LIST_INSERT_HEAD(&syncer_workitem_pending[queue][slot], bo,
1817 bo_synclist);
1818 mtx_unlock(&sync_mtx);
1819 }
1820
1821 static int
1822 sysctl_vfs_worklist_len(SYSCTL_HANDLER_ARGS)
1823 {
1824 int error, len;
1825
1826 mtx_lock(&sync_mtx);
1827 len = syncer_worklist_len - sync_vnode_count;
1828 mtx_unlock(&sync_mtx);
1829 error = SYSCTL_OUT(req, &len, sizeof(len));
1830 return (error);
1831 }
1832
1833 SYSCTL_PROC(_vfs, OID_AUTO, worklist_len, CTLTYPE_INT | CTLFLAG_RD, NULL, 0,
1834 sysctl_vfs_worklist_len, "I", "Syncer thread worklist length");
1835
1836 static struct proc *updateproc;
1837 static void sched_sync(void);
1838 static struct kproc_desc up_kp = {
1839 "syncer",
1840 sched_sync,
1841 &updateproc
1842 };
1843 SYSINIT(syncer, SI_SUB_KTHREAD_UPDATE, SI_ORDER_FIRST, kproc_start, &up_kp);
1844
1845 static int
1846 sync_vnode(struct synclist *slp, struct bufobj **bo, struct thread *td)
1847 {
1848 struct vnode *vp;
1849 struct mount *mp;
1850
1851 *bo = LIST_FIRST(slp);
1852 if (*bo == NULL)
1853 return (0);
1854 vp = (*bo)->__bo_vnode; /* XXX */
1855 if (VOP_ISLOCKED(vp) != 0 || VI_TRYLOCK(vp) == 0)
1856 return (1);
1857 /*
1858 * We use vhold in case the vnode does not
1859 * successfully sync. vhold prevents the vnode from
1860 * going away when we unlock the sync_mtx so that
1861 * we can acquire the vnode interlock.
1862 */
1863 vholdl(vp);
1864 mtx_unlock(&sync_mtx);
1865 VI_UNLOCK(vp);
1866 if (vn_start_write(vp, &mp, V_NOWAIT) != 0) {
1867 vdrop(vp);
1868 mtx_lock(&sync_mtx);
1869 return (*bo == LIST_FIRST(slp));
1870 }
1871 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
1872 (void) VOP_FSYNC(vp, MNT_LAZY, td);
1873 VOP_UNLOCK(vp, 0);
1874 vn_finished_write(mp);
1875 BO_LOCK(*bo);
1876 if (((*bo)->bo_flag & BO_ONWORKLST) != 0) {
1877 /*
1878 * Put us back on the worklist. The worklist
1879 * routine will remove us from our current
1880 * position and then add us back in at a later
1881 * position.
1882 */
1883 vn_syncer_add_to_worklist(*bo, syncdelay);
1884 }
1885 BO_UNLOCK(*bo);
1886 vdrop(vp);
1887 mtx_lock(&sync_mtx);
1888 return (0);
1889 }
1890
1891 /*
1892 * System filesystem synchronizer daemon.
1893 */
1894 static void
1895 sched_sync(void)
1896 {
1897 struct synclist *gnext, *next;
1898 struct synclist *gslp, *slp;
1899 struct bufobj *bo;
1900 long starttime;
1901 struct thread *td = curthread;
1902 int last_work_seen;
1903 int net_worklist_len;
1904 int syncer_final_iter;
1905 int first_printf;
1906 int error;
1907
1908 last_work_seen = 0;
1909 syncer_final_iter = 0;
1910 first_printf = 1;
1911 syncer_state = SYNCER_RUNNING;
1912 starttime = time_uptime;
1913 td->td_pflags |= TDP_NORUNNINGBUF;
1914
1915 EVENTHANDLER_REGISTER(shutdown_pre_sync, syncer_shutdown, td->td_proc,
1916 SHUTDOWN_PRI_LAST);
1917
1918 mtx_lock(&sync_mtx);
1919 for (;;) {
1920 if (syncer_state == SYNCER_FINAL_DELAY &&
1921 syncer_final_iter == 0) {
1922 mtx_unlock(&sync_mtx);
1923 kproc_suspend_check(td->td_proc);
1924 mtx_lock(&sync_mtx);
1925 }
1926 net_worklist_len = syncer_worklist_len - sync_vnode_count;
1927 if (syncer_state != SYNCER_RUNNING &&
1928 starttime != time_uptime) {
1929 if (first_printf) {
1930 printf("\nSyncing disks, vnodes remaining...");
1931 first_printf = 0;
1932 }
1933 printf("%d ", net_worklist_len);
1934 }
1935 starttime = time_uptime;
1936
1937 /*
1938 * Push files whose dirty time has expired. Be careful
1939 * of interrupt race on slp queue.
1940 *
1941 * Skip over empty worklist slots when shutting down.
1942 */
1943 do {
1944 slp = &syncer_workitem_pending[WI_MPSAFEQ][syncer_delayno];
1945 gslp = &syncer_workitem_pending[WI_GIANTQ][syncer_delayno];
1946 syncer_delayno += 1;
1947 if (syncer_delayno == syncer_maxdelay)
1948 syncer_delayno = 0;
1949 next = &syncer_workitem_pending[WI_MPSAFEQ][syncer_delayno];
1950 gnext = &syncer_workitem_pending[WI_GIANTQ][syncer_delayno];
1951 /*
1952 * If the worklist has wrapped since the
1953 * it was emptied of all but syncer vnodes,
1954 * switch to the FINAL_DELAY state and run
1955 * for one more second.
1956 */
1957 if (syncer_state == SYNCER_SHUTTING_DOWN &&
1958 net_worklist_len == 0 &&
1959 last_work_seen == syncer_delayno) {
1960 syncer_state = SYNCER_FINAL_DELAY;
1961 syncer_final_iter = SYNCER_SHUTDOWN_SPEEDUP;
1962 }
1963 } while (syncer_state != SYNCER_RUNNING && LIST_EMPTY(slp) &&
1964 LIST_EMPTY(gslp) && syncer_worklist_len > 0);
1965
1966 /*
1967 * Keep track of the last time there was anything
1968 * on the worklist other than syncer vnodes.
1969 * Return to the SHUTTING_DOWN state if any
1970 * new work appears.
1971 */
1972 if (net_worklist_len > 0 || syncer_state == SYNCER_RUNNING)
1973 last_work_seen = syncer_delayno;
1974 if (net_worklist_len > 0 && syncer_state == SYNCER_FINAL_DELAY)
1975 syncer_state = SYNCER_SHUTTING_DOWN;
1976 while (!LIST_EMPTY(slp)) {
1977 error = sync_vnode(slp, &bo, td);
1978 if (error == 1) {
1979 LIST_REMOVE(bo, bo_synclist);
1980 LIST_INSERT_HEAD(next, bo, bo_synclist);
1981 continue;
1982 }
1983
1984 if (first_printf == 0)
1985 wdog_kern_pat(WD_LASTVAL);
1986
1987 }
1988 if (!LIST_EMPTY(gslp)) {
1989 mtx_unlock(&sync_mtx);
1990 mtx_lock(&Giant);
1991 mtx_lock(&sync_mtx);
1992 while (!LIST_EMPTY(gslp)) {
1993 error = sync_vnode(gslp, &bo, td);
1994 if (error == 1) {
1995 LIST_REMOVE(bo, bo_synclist);
1996 LIST_INSERT_HEAD(gnext, bo,
1997 bo_synclist);
1998 continue;
1999 }
2000 }
2001 mtx_unlock(&Giant);
2002 }
2003 if (syncer_state == SYNCER_FINAL_DELAY && syncer_final_iter > 0)
2004 syncer_final_iter--;
2005 /*
2006 * The variable rushjob allows the kernel to speed up the
2007 * processing of the filesystem syncer process. A rushjob
2008 * value of N tells the filesystem syncer to process the next
2009 * N seconds worth of work on its queue ASAP. Currently rushjob
2010 * is used by the soft update code to speed up the filesystem
2011 * syncer process when the incore state is getting so far
2012 * ahead of the disk that the kernel memory pool is being
2013 * threatened with exhaustion.
2014 */
2015 if (rushjob > 0) {
2016 rushjob -= 1;
2017 continue;
2018 }
2019 /*
2020 * Just sleep for a short period of time between
2021 * iterations when shutting down to allow some I/O
2022 * to happen.
2023 *
2024 * If it has taken us less than a second to process the
2025 * current work, then wait. Otherwise start right over
2026 * again. We can still lose time if any single round
2027 * takes more than two seconds, but it does not really
2028 * matter as we are just trying to generally pace the
2029 * filesystem activity.
2030 */
2031 if (syncer_state != SYNCER_RUNNING ||
2032 time_uptime == starttime) {
2033 thread_lock(td);
2034 sched_prio(td, PPAUSE);
2035 thread_unlock(td);
2036 }
2037 if (syncer_state != SYNCER_RUNNING)
2038 cv_timedwait(&sync_wakeup, &sync_mtx,
2039 hz / SYNCER_SHUTDOWN_SPEEDUP);
2040 else if (time_uptime == starttime)
2041 cv_timedwait(&sync_wakeup, &sync_mtx, hz);
2042 }
2043 }
2044
2045 /*
2046 * Request the syncer daemon to speed up its work.
2047 * We never push it to speed up more than half of its
2048 * normal turn time, otherwise it could take over the cpu.
2049 */
2050 int
2051 speedup_syncer(void)
2052 {
2053 int ret = 0;
2054
2055 mtx_lock(&sync_mtx);
2056 if (rushjob < syncdelay / 2) {
2057 rushjob += 1;
2058 stat_rush_requests += 1;
2059 ret = 1;
2060 }
2061 mtx_unlock(&sync_mtx);
2062 cv_broadcast(&sync_wakeup);
2063 return (ret);
2064 }
2065
2066 /*
2067 * Tell the syncer to speed up its work and run though its work
2068 * list several times, then tell it to shut down.
2069 */
2070 static void
2071 syncer_shutdown(void *arg, int howto)
2072 {
2073
2074 if (howto & RB_NOSYNC)
2075 return;
2076 mtx_lock(&sync_mtx);
2077 syncer_state = SYNCER_SHUTTING_DOWN;
2078 rushjob = 0;
2079 mtx_unlock(&sync_mtx);
2080 cv_broadcast(&sync_wakeup);
2081 kproc_shutdown(arg, howto);
2082 }
2083
2084 /*
2085 * Reassign a buffer from one vnode to another.
2086 * Used to assign file specific control information
2087 * (indirect blocks) to the vnode to which they belong.
2088 */
2089 void
2090 reassignbuf(struct buf *bp)
2091 {
2092 struct vnode *vp;
2093 struct bufobj *bo;
2094 int delay;
2095 #ifdef INVARIANTS
2096 struct bufv *bv;
2097 #endif
2098
2099 vp = bp->b_vp;
2100 bo = bp->b_bufobj;
2101 ++reassignbufcalls;
2102
2103 CTR3(KTR_BUF, "reassignbuf(%p) vp %p flags %X",
2104 bp, bp->b_vp, bp->b_flags);
2105 /*
2106 * B_PAGING flagged buffers cannot be reassigned because their vp
2107 * is not fully linked in.
2108 */
2109 if (bp->b_flags & B_PAGING)
2110 panic("cannot reassign paging buffer");
2111
2112 /*
2113 * Delete from old vnode list, if on one.
2114 */
2115 BO_LOCK(bo);
2116 if (bp->b_xflags & (BX_VNDIRTY | BX_VNCLEAN))
2117 buf_vlist_remove(bp);
2118 else
2119 panic("reassignbuf: Buffer %p not on queue.", bp);
2120 /*
2121 * If dirty, put on list of dirty buffers; otherwise insert onto list
2122 * of clean buffers.
2123 */
2124 if (bp->b_flags & B_DELWRI) {
2125 if ((bo->bo_flag & BO_ONWORKLST) == 0) {
2126 switch (vp->v_type) {
2127 case VDIR:
2128 delay = dirdelay;
2129 break;
2130 case VCHR:
2131 delay = metadelay;
2132 break;
2133 default:
2134 delay = filedelay;
2135 }
2136 vn_syncer_add_to_worklist(bo, delay);
2137 }
2138 buf_vlist_add(bp, bo, BX_VNDIRTY);
2139 } else {
2140 buf_vlist_add(bp, bo, BX_VNCLEAN);
2141
2142 if ((bo->bo_flag & BO_ONWORKLST) && bo->bo_dirty.bv_cnt == 0) {
2143 mtx_lock(&sync_mtx);
2144 LIST_REMOVE(bo, bo_synclist);
2145 syncer_worklist_len--;
2146 mtx_unlock(&sync_mtx);
2147 bo->bo_flag &= ~BO_ONWORKLST;
2148 }
2149 }
2150 #ifdef INVARIANTS
2151 bv = &bo->bo_clean;
2152 bp = TAILQ_FIRST(&bv->bv_hd);
2153 KASSERT(bp == NULL || bp->b_bufobj == bo,
2154 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo));
2155 bp = TAILQ_LAST(&bv->bv_hd, buflists);
2156 KASSERT(bp == NULL || bp->b_bufobj == bo,
2157 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo));
2158 bv = &bo->bo_dirty;
2159 bp = TAILQ_FIRST(&bv->bv_hd);
2160 KASSERT(bp == NULL || bp->b_bufobj == bo,
2161 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo));
2162 bp = TAILQ_LAST(&bv->bv_hd, buflists);
2163 KASSERT(bp == NULL || bp->b_bufobj == bo,
2164 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo));
2165 #endif
2166 BO_UNLOCK(bo);
2167 }
2168
2169 /*
2170 * Increment the use and hold counts on the vnode, taking care to reference
2171 * the driver's usecount if this is a chardev. The vholdl() will remove
2172 * the vnode from the free list if it is presently free. Requires the
2173 * vnode interlock and returns with it held.
2174 */
2175 static void
2176 v_incr_usecount(struct vnode *vp)
2177 {
2178
2179 CTR2(KTR_VFS, "%s: vp %p", __func__, vp);
2180 vp->v_usecount++;
2181 if (vp->v_type == VCHR && vp->v_rdev != NULL) {
2182 dev_lock();
2183 vp->v_rdev->si_usecount++;
2184 dev_unlock();
2185 }
2186 vholdl(vp);
2187 }
2188
2189 /*
2190 * Turn a holdcnt into a use+holdcnt such that only one call to
2191 * v_decr_usecount is needed.
2192 */
2193 static void
2194 v_upgrade_usecount(struct vnode *vp)
2195 {
2196
2197 CTR2(KTR_VFS, "%s: vp %p", __func__, vp);
2198 vp->v_usecount++;
2199 if (vp->v_type == VCHR && vp->v_rdev != NULL) {
2200 dev_lock();
2201 vp->v_rdev->si_usecount++;
2202 dev_unlock();
2203 }
2204 }
2205
2206 /*
2207 * Decrement the vnode use and hold count along with the driver's usecount
2208 * if this is a chardev. The vdropl() below releases the vnode interlock
2209 * as it may free the vnode.
2210 */
2211 static void
2212 v_decr_usecount(struct vnode *vp)
2213 {
2214
2215 ASSERT_VI_LOCKED(vp, __FUNCTION__);
2216 VNASSERT(vp->v_usecount > 0, vp,
2217 ("v_decr_usecount: negative usecount"));
2218 CTR2(KTR_VFS, "%s: vp %p", __func__, vp);
2219 vp->v_usecount--;
2220 if (vp->v_type == VCHR && vp->v_rdev != NULL) {
2221 dev_lock();
2222 vp->v_rdev->si_usecount--;
2223 dev_unlock();
2224 }
2225 vdropl(vp);
2226 }
2227
2228 /*
2229 * Decrement only the use count and driver use count. This is intended to
2230 * be paired with a follow on vdropl() to release the remaining hold count.
2231 * In this way we may vgone() a vnode with a 0 usecount without risk of
2232 * having it end up on a free list because the hold count is kept above 0.
2233 */
2234 static void
2235 v_decr_useonly(struct vnode *vp)
2236 {
2237
2238 ASSERT_VI_LOCKED(vp, __FUNCTION__);
2239 VNASSERT(vp->v_usecount > 0, vp,
2240 ("v_decr_useonly: negative usecount"));
2241 CTR2(KTR_VFS, "%s: vp %p", __func__, vp);
2242 vp->v_usecount--;
2243 if (vp->v_type == VCHR && vp->v_rdev != NULL) {
2244 dev_lock();
2245 vp->v_rdev->si_usecount--;
2246 dev_unlock();
2247 }
2248 }
2249
2250 /*
2251 * Grab a particular vnode from the free list, increment its
2252 * reference count and lock it. VI_DOOMED is set if the vnode
2253 * is being destroyed. Only callers who specify LK_RETRY will
2254 * see doomed vnodes. If inactive processing was delayed in
2255 * vput try to do it here.
2256 */
2257 int
2258 vget(struct vnode *vp, int flags, struct thread *td)
2259 {
2260 int error;
2261
2262 error = 0;
2263 VFS_ASSERT_GIANT(vp->v_mount);
2264 VNASSERT((flags & LK_TYPE_MASK) != 0, vp,
2265 ("vget: invalid lock operation"));
2266 CTR3(KTR_VFS, "%s: vp %p with flags %d", __func__, vp, flags);
2267
2268 if ((flags & LK_INTERLOCK) == 0)
2269 VI_LOCK(vp);
2270 vholdl(vp);
2271 if ((error = vn_lock(vp, flags | LK_INTERLOCK)) != 0) {
2272 vdrop(vp);
2273 CTR2(KTR_VFS, "%s: impossible to lock vnode %p", __func__,
2274 vp);
2275 return (error);
2276 }
2277 if (vp->v_iflag & VI_DOOMED && (flags & LK_RETRY) == 0)
2278 panic("vget: vn_lock failed to return ENOENT\n");
2279 VI_LOCK(vp);
2280 /* Upgrade our holdcnt to a usecount. */
2281 v_upgrade_usecount(vp);
2282 /*
2283 * We don't guarantee that any particular close will
2284 * trigger inactive processing so just make a best effort
2285 * here at preventing a reference to a removed file. If
2286 * we don't succeed no harm is done.
2287 */
2288 if (vp->v_iflag & VI_OWEINACT) {
2289 if (VOP_ISLOCKED(vp) == LK_EXCLUSIVE &&
2290 (flags & LK_NOWAIT) == 0)
2291 vinactive(vp, td);
2292 vp->v_iflag &= ~VI_OWEINACT;
2293 }
2294 VI_UNLOCK(vp);
2295 return (0);
2296 }
2297
2298 /*
2299 * Increase the reference count of a vnode.
2300 */
2301 void
2302 vref(struct vnode *vp)
2303 {
2304
2305 CTR2(KTR_VFS, "%s: vp %p", __func__, vp);
2306 VI_LOCK(vp);
2307 v_incr_usecount(vp);
2308 VI_UNLOCK(vp);
2309 }
2310
2311 /*
2312 * Return reference count of a vnode.
2313 *
2314 * The results of this call are only guaranteed when some mechanism other
2315 * than the VI lock is used to stop other processes from gaining references
2316 * to the vnode. This may be the case if the caller holds the only reference.
2317 * This is also useful when stale data is acceptable as race conditions may
2318 * be accounted for by some other means.
2319 */
2320 int
2321 vrefcnt(struct vnode *vp)
2322 {
2323 int usecnt;
2324
2325 VI_LOCK(vp);
2326 usecnt = vp->v_usecount;
2327 VI_UNLOCK(vp);
2328
2329 return (usecnt);
2330 }
2331
2332 #define VPUTX_VRELE 1
2333 #define VPUTX_VPUT 2
2334 #define VPUTX_VUNREF 3
2335
2336 static void
2337 vputx(struct vnode *vp, int func)
2338 {
2339 int error;
2340
2341 KASSERT(vp != NULL, ("vputx: null vp"));
2342 if (func == VPUTX_VUNREF)
2343 ASSERT_VOP_LOCKED(vp, "vunref");
2344 else if (func == VPUTX_VPUT)
2345 ASSERT_VOP_LOCKED(vp, "vput");
2346 else
2347 KASSERT(func == VPUTX_VRELE, ("vputx: wrong func"));
2348 VFS_ASSERT_GIANT(vp->v_mount);
2349 CTR2(KTR_VFS, "%s: vp %p", __func__, vp);
2350 VI_LOCK(vp);
2351
2352 /* Skip this v_writecount check if we're going to panic below. */
2353 VNASSERT(vp->v_writecount < vp->v_usecount || vp->v_usecount < 1, vp,
2354 ("vputx: missed vn_close"));
2355 error = 0;
2356
2357 if (vp->v_usecount > 1 || ((vp->v_iflag & VI_DOINGINACT) &&
2358 vp->v_usecount == 1)) {
2359 if (func == VPUTX_VPUT)
2360 VOP_UNLOCK(vp, 0);
2361 v_decr_usecount(vp);
2362 return;
2363 }
2364
2365 if (vp->v_usecount != 1) {
2366 vprint("vputx: negative ref count", vp);
2367 panic("vputx: negative ref cnt");
2368 }
2369 CTR2(KTR_VFS, "%s: return vnode %p to the freelist", __func__, vp);
2370 /*
2371 * We want to hold the vnode until the inactive finishes to
2372 * prevent vgone() races. We drop the use count here and the
2373 * hold count below when we're done.
2374 */
2375 v_decr_useonly(vp);
2376 /*
2377 * We must call VOP_INACTIVE with the node locked. Mark
2378 * as VI_DOINGINACT to avoid recursion.
2379 */
2380 vp->v_iflag |= VI_OWEINACT;
2381 switch (func) {
2382 case VPUTX_VRELE:
2383 error = vn_lock(vp, LK_EXCLUSIVE | LK_INTERLOCK);
2384 VI_LOCK(vp);
2385 break;
2386 case VPUTX_VPUT:
2387 if (VOP_ISLOCKED(vp) != LK_EXCLUSIVE) {
2388 error = VOP_LOCK(vp, LK_UPGRADE | LK_INTERLOCK |
2389 LK_NOWAIT);
2390 VI_LOCK(vp);
2391 }
2392 break;
2393 case VPUTX_VUNREF:
2394 if (VOP_ISLOCKED(vp) != LK_EXCLUSIVE) {
2395 error = VOP_LOCK(vp, LK_TRYUPGRADE | LK_INTERLOCK);
2396 VI_LOCK(vp);
2397 }
2398 break;
2399 }
2400 if (vp->v_usecount > 0)
2401 vp->v_iflag &= ~VI_OWEINACT;
2402 if (error == 0) {
2403 if (vp->v_iflag & VI_OWEINACT)
2404 vinactive(vp, curthread);
2405 if (func != VPUTX_VUNREF)
2406 VOP_UNLOCK(vp, 0);
2407 }
2408 vdropl(vp);
2409 }
2410
2411 /*
2412 * Vnode put/release.
2413 * If count drops to zero, call inactive routine and return to freelist.
2414 */
2415 void
2416 vrele(struct vnode *vp)
2417 {
2418
2419 vputx(vp, VPUTX_VRELE);
2420 }
2421
2422 /*
2423 * Release an already locked vnode. This give the same effects as
2424 * unlock+vrele(), but takes less time and avoids releasing and
2425 * re-aquiring the lock (as vrele() acquires the lock internally.)
2426 */
2427 void
2428 vput(struct vnode *vp)
2429 {
2430
2431 vputx(vp, VPUTX_VPUT);
2432 }
2433
2434 /*
2435 * Release an exclusively locked vnode. Do not unlock the vnode lock.
2436 */
2437 void
2438 vunref(struct vnode *vp)
2439 {
2440
2441 vputx(vp, VPUTX_VUNREF);
2442 }
2443
2444 /*
2445 * Somebody doesn't want the vnode recycled.
2446 */
2447 void
2448 vhold(struct vnode *vp)
2449 {
2450
2451 VI_LOCK(vp);
2452 vholdl(vp);
2453 VI_UNLOCK(vp);
2454 }
2455
2456 /*
2457 * Increase the hold count and activate if this is the first reference.
2458 */
2459 void
2460 vholdl(struct vnode *vp)
2461 {
2462 struct mount *mp;
2463
2464 CTR2(KTR_VFS, "%s: vp %p", __func__, vp);
2465 vp->v_holdcnt++;
2466 if (!VSHOULDBUSY(vp))
2467 return;
2468 ASSERT_VI_LOCKED(vp, "vholdl");
2469 VNASSERT((vp->v_iflag & VI_FREE) != 0, vp, ("vnode not free"));
2470 VNASSERT(vp->v_op != NULL, vp, ("vholdl: vnode already reclaimed."));
2471 /*
2472 * Remove a vnode from the free list, mark it as in use,
2473 * and put it on the active list.
2474 */
2475 mtx_lock(&vnode_free_list_mtx);
2476 TAILQ_REMOVE(&vnode_free_list, vp, v_actfreelist);
2477 freevnodes--;
2478 vp->v_iflag &= ~(VI_FREE|VI_AGE);
2479 KASSERT((vp->v_iflag & VI_ACTIVE) == 0,
2480 ("Activating already active vnode"));
2481 vp->v_iflag |= VI_ACTIVE;
2482 mp = vp->v_mount;
2483 TAILQ_INSERT_HEAD(&mp->mnt_activevnodelist, vp, v_actfreelist);
2484 mp->mnt_activevnodelistsize++;
2485 mtx_unlock(&vnode_free_list_mtx);
2486 }
2487
2488 /*
2489 * Note that there is one less who cares about this vnode.
2490 * vdrop() is the opposite of vhold().
2491 */
2492 void
2493 vdrop(struct vnode *vp)
2494 {
2495
2496 VI_LOCK(vp);
2497 vdropl(vp);
2498 }
2499
2500 /*
2501 * Drop the hold count of the vnode. If this is the last reference to
2502 * the vnode we place it on the free list unless it has been vgone'd
2503 * (marked VI_DOOMED) in which case we will free it.
2504 */
2505 void
2506 vdropl(struct vnode *vp)
2507 {
2508 struct bufobj *bo;
2509 struct mount *mp;
2510 int active;
2511
2512 ASSERT_VI_LOCKED(vp, "vdropl");
2513 CTR2(KTR_VFS, "%s: vp %p", __func__, vp);
2514 if (vp->v_holdcnt <= 0)
2515 panic("vdrop: holdcnt %d", vp->v_holdcnt);
2516 vp->v_holdcnt--;
2517 if (vp->v_holdcnt > 0) {
2518 VI_UNLOCK(vp);
2519 return;
2520 }
2521 if ((vp->v_iflag & VI_DOOMED) == 0) {
2522 /*
2523 * Mark a vnode as free: remove it from its active list
2524 * and put it up for recycling on the freelist.
2525 */
2526 VNASSERT(vp->v_op != NULL, vp,
2527 ("vdropl: vnode already reclaimed."));
2528 VNASSERT((vp->v_iflag & VI_FREE) == 0, vp,
2529 ("vnode already free"));
2530 VNASSERT(VSHOULDFREE(vp), vp,
2531 ("vdropl: freeing when we shouldn't"));
2532 active = vp->v_iflag & VI_ACTIVE;
2533 vp->v_iflag &= ~VI_ACTIVE;
2534 mp = vp->v_mount;
2535 mtx_lock(&vnode_free_list_mtx);
2536 if (active) {
2537 TAILQ_REMOVE(&mp->mnt_activevnodelist, vp,
2538 v_actfreelist);
2539 mp->mnt_activevnodelistsize--;
2540 }
2541 if (vp->v_iflag & VI_AGE) {
2542 TAILQ_INSERT_HEAD(&vnode_free_list, vp, v_actfreelist);
2543 } else {
2544 TAILQ_INSERT_TAIL(&vnode_free_list, vp, v_actfreelist);
2545 }
2546 freevnodes++;
2547 vp->v_iflag &= ~VI_AGE;
2548 vp->v_iflag |= VI_FREE;
2549 mtx_unlock(&vnode_free_list_mtx);
2550 VI_UNLOCK(vp);
2551 return;
2552 }
2553 /*
2554 * The vnode has been marked for destruction, so free it.
2555 */
2556 CTR2(KTR_VFS, "%s: destroying the vnode %p", __func__, vp);
2557 atomic_subtract_long(&numvnodes, 1);
2558 bo = &vp->v_bufobj;
2559 VNASSERT((vp->v_iflag & VI_FREE) == 0, vp,
2560 ("cleaned vnode still on the free list."));
2561 VNASSERT(vp->v_data == NULL, vp, ("cleaned vnode isn't"));
2562 VNASSERT(vp->v_holdcnt == 0, vp, ("Non-zero hold count"));
2563 VNASSERT(vp->v_usecount == 0, vp, ("Non-zero use count"));
2564 VNASSERT(vp->v_writecount == 0, vp, ("Non-zero write count"));
2565 VNASSERT(bo->bo_numoutput == 0, vp, ("Clean vnode has pending I/O's"));
2566 VNASSERT(bo->bo_clean.bv_cnt == 0, vp, ("cleanbufcnt not 0"));
2567 VNASSERT(bo->bo_clean.bv_root == NULL, vp, ("cleanblkroot not NULL"));
2568 VNASSERT(bo->bo_dirty.bv_cnt == 0, vp, ("dirtybufcnt not 0"));
2569 VNASSERT(bo->bo_dirty.bv_root == NULL, vp, ("dirtyblkroot not NULL"));
2570 VNASSERT(TAILQ_EMPTY(&vp->v_cache_dst), vp, ("vp has namecache dst"));
2571 VNASSERT(LIST_EMPTY(&vp->v_cache_src), vp, ("vp has namecache src"));
2572 VNASSERT(vp->v_cache_dd == NULL, vp, ("vp has namecache for .."));
2573 VI_UNLOCK(vp);
2574 #ifdef MAC
2575 mac_vnode_destroy(vp);
2576 #endif
2577 if (vp->v_pollinfo != NULL)
2578 destroy_vpollinfo(vp->v_pollinfo);
2579 #ifdef INVARIANTS
2580 /* XXX Elsewhere we detect an already freed vnode via NULL v_op. */
2581 vp->v_op = NULL;
2582 #endif
2583 rangelock_destroy(&vp->v_rl);
2584 lockdestroy(vp->v_vnlock);
2585 mtx_destroy(&vp->v_interlock);
2586 mtx_destroy(BO_MTX(bo));
2587 uma_zfree(vnode_zone, vp);
2588 }
2589
2590 /*
2591 * Call VOP_INACTIVE on the vnode and manage the DOINGINACT and OWEINACT
2592 * flags. DOINGINACT prevents us from recursing in calls to vinactive.
2593 * OWEINACT tracks whether a vnode missed a call to inactive due to a
2594 * failed lock upgrade.
2595 */
2596 void
2597 vinactive(struct vnode *vp, struct thread *td)
2598 {
2599 struct vm_object *obj;
2600
2601 ASSERT_VOP_ELOCKED(vp, "vinactive");
2602 ASSERT_VI_LOCKED(vp, "vinactive");
2603 VNASSERT((vp->v_iflag & VI_DOINGINACT) == 0, vp,
2604 ("vinactive: recursed on VI_DOINGINACT"));
2605 CTR2(KTR_VFS, "%s: vp %p", __func__, vp);
2606 vp->v_iflag |= VI_DOINGINACT;
2607 vp->v_iflag &= ~VI_OWEINACT;
2608 VI_UNLOCK(vp);
2609 /*
2610 * Before moving off the active list, we must be sure that any
2611 * modified pages are on the vnode's dirty list since these will
2612 * no longer be checked once the vnode is on the inactive list.
2613 * Because the vnode vm object keeps a hold reference on the vnode
2614 * if there is at least one resident non-cached page, the vnode
2615 * cannot leave the active list without the page cleanup done.
2616 */
2617 obj = vp->v_object;
2618 if (obj != NULL && (obj->flags & OBJ_MIGHTBEDIRTY) != 0) {
2619 VM_OBJECT_LOCK(obj);
2620 vm_object_page_clean(obj, 0, 0, OBJPC_NOSYNC);
2621 VM_OBJECT_UNLOCK(obj);
2622 }
2623 VOP_INACTIVE(vp, td);
2624 VI_LOCK(vp);
2625 VNASSERT(vp->v_iflag & VI_DOINGINACT, vp,
2626 ("vinactive: lost VI_DOINGINACT"));
2627 vp->v_iflag &= ~VI_DOINGINACT;
2628 }
2629
2630 /*
2631 * Remove any vnodes in the vnode table belonging to mount point mp.
2632 *
2633 * If FORCECLOSE is not specified, there should not be any active ones,
2634 * return error if any are found (nb: this is a user error, not a
2635 * system error). If FORCECLOSE is specified, detach any active vnodes
2636 * that are found.
2637 *
2638 * If WRITECLOSE is set, only flush out regular file vnodes open for
2639 * writing.
2640 *
2641 * SKIPSYSTEM causes any vnodes marked VV_SYSTEM to be skipped.
2642 *
2643 * `rootrefs' specifies the base reference count for the root vnode
2644 * of this filesystem. The root vnode is considered busy if its
2645 * v_usecount exceeds this value. On a successful return, vflush(, td)
2646 * will call vrele() on the root vnode exactly rootrefs times.
2647 * If the SKIPSYSTEM or WRITECLOSE flags are specified, rootrefs must
2648 * be zero.
2649 */
2650 #ifdef DIAGNOSTIC
2651 static int busyprt = 0; /* print out busy vnodes */
2652 SYSCTL_INT(_debug, OID_AUTO, busyprt, CTLFLAG_RW, &busyprt, 0, "Print out busy vnodes");
2653 #endif
2654
2655 int
2656 vflush(struct mount *mp, int rootrefs, int flags, struct thread *td)
2657 {
2658 struct vnode *vp, *mvp, *rootvp = NULL;
2659 struct vattr vattr;
2660 int busy = 0, error;
2661
2662 CTR4(KTR_VFS, "%s: mp %p with rootrefs %d and flags %d", __func__, mp,
2663 rootrefs, flags);
2664 if (rootrefs > 0) {
2665 KASSERT((flags & (SKIPSYSTEM | WRITECLOSE)) == 0,
2666 ("vflush: bad args"));
2667 /*
2668 * Get the filesystem root vnode. We can vput() it
2669 * immediately, since with rootrefs > 0, it won't go away.
2670 */
2671 if ((error = VFS_ROOT(mp, LK_EXCLUSIVE, &rootvp)) != 0) {
2672 CTR2(KTR_VFS, "%s: vfs_root lookup failed with %d",
2673 __func__, error);
2674 return (error);
2675 }
2676 vput(rootvp);
2677 }
2678 loop:
2679 MNT_VNODE_FOREACH_ALL(vp, mp, mvp) {
2680 vholdl(vp);
2681 error = vn_lock(vp, LK_INTERLOCK | LK_EXCLUSIVE);
2682 if (error) {
2683 vdrop(vp);
2684 MNT_VNODE_FOREACH_ALL_ABORT(mp, mvp);
2685 goto loop;
2686 }
2687 /*
2688 * Skip over a vnodes marked VV_SYSTEM.
2689 */
2690 if ((flags & SKIPSYSTEM) && (vp->v_vflag & VV_SYSTEM)) {
2691 VOP_UNLOCK(vp, 0);
2692 vdrop(vp);
2693 continue;
2694 }
2695 /*
2696 * If WRITECLOSE is set, flush out unlinked but still open
2697 * files (even if open only for reading) and regular file
2698 * vnodes open for writing.
2699 */
2700 if (flags & WRITECLOSE) {
2701 if (vp->v_object != NULL) {
2702 VM_OBJECT_LOCK(vp->v_object);
2703 vm_object_page_clean(vp->v_object, 0, 0, 0);
2704 VM_OBJECT_UNLOCK(vp->v_object);
2705 }
2706 error = VOP_FSYNC(vp, MNT_WAIT, td);
2707 if (error != 0) {
2708 VOP_UNLOCK(vp, 0);
2709 vdrop(vp);
2710 MNT_VNODE_FOREACH_ALL_ABORT(mp, mvp);
2711 return (error);
2712 }
2713 error = VOP_GETATTR(vp, &vattr, td->td_ucred);
2714 VI_LOCK(vp);
2715
2716 if ((vp->v_type == VNON ||
2717 (error == 0 && vattr.va_nlink > 0)) &&
2718 (vp->v_writecount == 0 || vp->v_type != VREG)) {
2719 VOP_UNLOCK(vp, 0);
2720 vdropl(vp);
2721 continue;
2722 }
2723 } else
2724 VI_LOCK(vp);
2725 /*
2726 * With v_usecount == 0, all we need to do is clear out the
2727 * vnode data structures and we are done.
2728 *
2729 * If FORCECLOSE is set, forcibly close the vnode.
2730 */
2731 if (vp->v_usecount == 0 || (flags & FORCECLOSE)) {
2732 VNASSERT(vp->v_usecount == 0 ||
2733 (vp->v_type != VCHR && vp->v_type != VBLK), vp,
2734 ("device VNODE %p is FORCECLOSED", vp));
2735 vgonel(vp);
2736 } else {
2737 busy++;
2738 #ifdef DIAGNOSTIC
2739 if (busyprt)
2740 vprint("vflush: busy vnode", vp);
2741 #endif
2742 }
2743 VOP_UNLOCK(vp, 0);
2744 vdropl(vp);
2745 }
2746 if (rootrefs > 0 && (flags & FORCECLOSE) == 0) {
2747 /*
2748 * If just the root vnode is busy, and if its refcount
2749 * is equal to `rootrefs', then go ahead and kill it.
2750 */
2751 VI_LOCK(rootvp);
2752 KASSERT(busy > 0, ("vflush: not busy"));
2753 VNASSERT(rootvp->v_usecount >= rootrefs, rootvp,
2754 ("vflush: usecount %d < rootrefs %d",
2755 rootvp->v_usecount, rootrefs));
2756 if (busy == 1 && rootvp->v_usecount == rootrefs) {
2757 VOP_LOCK(rootvp, LK_EXCLUSIVE|LK_INTERLOCK);
2758 vgone(rootvp);
2759 VOP_UNLOCK(rootvp, 0);
2760 busy = 0;
2761 } else
2762 VI_UNLOCK(rootvp);
2763 }
2764 if (busy) {
2765 CTR2(KTR_VFS, "%s: failing as %d vnodes are busy", __func__,
2766 busy);
2767 return (EBUSY);
2768 }
2769 for (; rootrefs > 0; rootrefs--)
2770 vrele(rootvp);
2771 return (0);
2772 }
2773
2774 /*
2775 * Recycle an unused vnode to the front of the free list.
2776 */
2777 int
2778 vrecycle(struct vnode *vp, struct thread *td)
2779 {
2780 int recycled;
2781
2782 ASSERT_VOP_ELOCKED(vp, "vrecycle");
2783 CTR2(KTR_VFS, "%s: vp %p", __func__, vp);
2784 recycled = 0;
2785 VI_LOCK(vp);
2786 if (vp->v_usecount == 0) {
2787 recycled = 1;
2788 vgonel(vp);
2789 }
2790 VI_UNLOCK(vp);
2791 return (recycled);
2792 }
2793
2794 /*
2795 * Eliminate all activity associated with a vnode
2796 * in preparation for reuse.
2797 */
2798 void
2799 vgone(struct vnode *vp)
2800 {
2801 VI_LOCK(vp);
2802 vgonel(vp);
2803 VI_UNLOCK(vp);
2804 }
2805
2806 static void
2807 notify_lowervp_vfs_dummy(struct mount *mp __unused,
2808 struct vnode *lowervp __unused)
2809 {
2810 }
2811
2812 /*
2813 * Notify upper mounts about reclaimed or unlinked vnode.
2814 */
2815 void
2816 vfs_notify_upper(struct vnode *vp, int event)
2817 {
2818 static struct vfsops vgonel_vfsops = {
2819 .vfs_reclaim_lowervp = notify_lowervp_vfs_dummy,
2820 .vfs_unlink_lowervp = notify_lowervp_vfs_dummy,
2821 };
2822 struct mount *mp, *ump, *mmp;
2823
2824 mp = vp->v_mount;
2825 if (mp == NULL)
2826 return;
2827
2828 MNT_ILOCK(mp);
2829 if (TAILQ_EMPTY(&mp->mnt_uppers))
2830 goto unlock;
2831 MNT_IUNLOCK(mp);
2832 mmp = malloc(sizeof(struct mount), M_TEMP, M_WAITOK | M_ZERO);
2833 mmp->mnt_op = &vgonel_vfsops;
2834 mmp->mnt_kern_flag |= MNTK_MARKER;
2835 MNT_ILOCK(mp);
2836 mp->mnt_kern_flag |= MNTK_VGONE_UPPER;
2837 for (ump = TAILQ_FIRST(&mp->mnt_uppers); ump != NULL;) {
2838 if ((ump->mnt_kern_flag & MNTK_MARKER) != 0) {
2839 ump = TAILQ_NEXT(ump, mnt_upper_link);
2840 continue;
2841 }
2842 TAILQ_INSERT_AFTER(&mp->mnt_uppers, ump, mmp, mnt_upper_link);
2843 MNT_IUNLOCK(mp);
2844 switch (event) {
2845 case VFS_NOTIFY_UPPER_RECLAIM:
2846 VFS_RECLAIM_LOWERVP(ump, vp);
2847 break;
2848 case VFS_NOTIFY_UPPER_UNLINK:
2849 VFS_UNLINK_LOWERVP(ump, vp);
2850 break;
2851 default:
2852 KASSERT(0, ("invalid event %d", event));
2853 break;
2854 }
2855 MNT_ILOCK(mp);
2856 ump = TAILQ_NEXT(mmp, mnt_upper_link);
2857 TAILQ_REMOVE(&mp->mnt_uppers, mmp, mnt_upper_link);
2858 }
2859 free(mmp, M_TEMP);
2860 mp->mnt_kern_flag &= ~MNTK_VGONE_UPPER;
2861 if ((mp->mnt_kern_flag & MNTK_VGONE_WAITER) != 0) {
2862 mp->mnt_kern_flag &= ~MNTK_VGONE_WAITER;
2863 wakeup(&mp->mnt_uppers);
2864 }
2865 unlock:
2866 MNT_IUNLOCK(mp);
2867 }
2868
2869 /*
2870 * vgone, with the vp interlock held.
2871 */
2872 void
2873 vgonel(struct vnode *vp)
2874 {
2875 struct thread *td;
2876 int oweinact;
2877 int active;
2878 struct mount *mp;
2879
2880 ASSERT_VOP_ELOCKED(vp, "vgonel");
2881 ASSERT_VI_LOCKED(vp, "vgonel");
2882 VNASSERT(vp->v_holdcnt, vp,
2883 ("vgonel: vp %p has no reference.", vp));
2884 CTR2(KTR_VFS, "%s: vp %p", __func__, vp);
2885 td = curthread;
2886
2887 /*
2888 * Don't vgonel if we're already doomed.
2889 */
2890 if (vp->v_iflag & VI_DOOMED)
2891 return;
2892 vp->v_iflag |= VI_DOOMED;
2893
2894 /*
2895 * Check to see if the vnode is in use. If so, we have to call
2896 * VOP_CLOSE() and VOP_INACTIVE().
2897 */
2898 active = vp->v_usecount;
2899 oweinact = (vp->v_iflag & VI_OWEINACT);
2900 VI_UNLOCK(vp);
2901 vfs_notify_upper(vp, VFS_NOTIFY_UPPER_RECLAIM);
2902
2903 /*
2904 * Clean out any buffers associated with the vnode.
2905 * If the flush fails, just toss the buffers.
2906 */
2907 mp = NULL;
2908 if (!TAILQ_EMPTY(&vp->v_bufobj.bo_dirty.bv_hd))
2909 (void) vn_start_secondary_write(vp, &mp, V_WAIT);
2910 if (vinvalbuf(vp, V_SAVE, 0, 0) != 0)
2911 vinvalbuf(vp, 0, 0, 0);
2912
2913 /*
2914 * If purging an active vnode, it must be closed and
2915 * deactivated before being reclaimed.
2916 */
2917 if (active)
2918 VOP_CLOSE(vp, FNONBLOCK, NOCRED, td);
2919 if (oweinact || active) {
2920 VI_LOCK(vp);
2921 if ((vp->v_iflag & VI_DOINGINACT) == 0)
2922 vinactive(vp, td);
2923 VI_UNLOCK(vp);
2924 }
2925 if (vp->v_type == VSOCK)
2926 vfs_unp_reclaim(vp);
2927 /*
2928 * Reclaim the vnode.
2929 */
2930 if (VOP_RECLAIM(vp, td))
2931 panic("vgone: cannot reclaim");
2932 if (mp != NULL)
2933 vn_finished_secondary_write(mp);
2934 VNASSERT(vp->v_object == NULL, vp,
2935 ("vop_reclaim left v_object vp=%p, tag=%s", vp, vp->v_tag));
2936 /*
2937 * Clear the advisory locks and wake up waiting threads.
2938 */
2939 (void)VOP_ADVLOCKPURGE(vp);
2940 /*
2941 * Delete from old mount point vnode list.
2942 */
2943 delmntque(vp);
2944 cache_purge(vp);
2945 /*
2946 * Done with purge, reset to the standard lock and invalidate
2947 * the vnode.
2948 */
2949 VI_LOCK(vp);
2950 vp->v_vnlock = &vp->v_lock;
2951 vp->v_op = &dead_vnodeops;
2952 vp->v_tag = "none";
2953 vp->v_type = VBAD;
2954 }
2955
2956 /*
2957 * Calculate the total number of references to a special device.
2958 */
2959 int
2960 vcount(struct vnode *vp)
2961 {
2962 int count;
2963
2964 dev_lock();
2965 count = vp->v_rdev->si_usecount;
2966 dev_unlock();
2967 return (count);
2968 }
2969
2970 /*
2971 * Same as above, but using the struct cdev *as argument
2972 */
2973 int
2974 count_dev(struct cdev *dev)
2975 {
2976 int count;
2977
2978 dev_lock();
2979 count = dev->si_usecount;
2980 dev_unlock();
2981 return(count);
2982 }
2983
2984 /*
2985 * Print out a description of a vnode.
2986 */
2987 static char *typename[] =
2988 {"VNON", "VREG", "VDIR", "VBLK", "VCHR", "VLNK", "VSOCK", "VFIFO", "VBAD",
2989 "VMARKER"};
2990
2991 void
2992 vn_printf(struct vnode *vp, const char *fmt, ...)
2993 {
2994 va_list ap;
2995 char buf[256], buf2[16];
2996 u_long flags;
2997
2998 va_start(ap, fmt);
2999 vprintf(fmt, ap);
3000 va_end(ap);
3001 printf("%p: ", (void *)vp);
3002 printf("tag %s, type %s\n", vp->v_tag, typename[vp->v_type]);
3003 printf(" usecount %d, writecount %d, refcount %d mountedhere %p\n",
3004 vp->v_usecount, vp->v_writecount, vp->v_holdcnt, vp->v_mountedhere);
3005 buf[0] = '\0';
3006 buf[1] = '\0';
3007 if (vp->v_vflag & VV_ROOT)
3008 strlcat(buf, "|VV_ROOT", sizeof(buf));
3009 if (vp->v_vflag & VV_ISTTY)
3010 strlcat(buf, "|VV_ISTTY", sizeof(buf));
3011 if (vp->v_vflag & VV_NOSYNC)
3012 strlcat(buf, "|VV_NOSYNC", sizeof(buf));
3013 if (vp->v_vflag & VV_ETERNALDEV)
3014 strlcat(buf, "|VV_ETERNALDEV", sizeof(buf));
3015 if (vp->v_vflag & VV_CACHEDLABEL)
3016 strlcat(buf, "|VV_CACHEDLABEL", sizeof(buf));
3017 if (vp->v_vflag & VV_TEXT)
3018 strlcat(buf, "|VV_TEXT", sizeof(buf));
3019 if (vp->v_vflag & VV_COPYONWRITE)
3020 strlcat(buf, "|VV_COPYONWRITE", sizeof(buf));
3021 if (vp->v_vflag & VV_SYSTEM)
3022 strlcat(buf, "|VV_SYSTEM", sizeof(buf));
3023 if (vp->v_vflag & VV_PROCDEP)
3024 strlcat(buf, "|VV_PROCDEP", sizeof(buf));
3025 if (vp->v_vflag & VV_NOKNOTE)
3026 strlcat(buf, "|VV_NOKNOTE", sizeof(buf));
3027 if (vp->v_vflag & VV_DELETED)
3028 strlcat(buf, "|VV_DELETED", sizeof(buf));
3029 if (vp->v_vflag & VV_MD)
3030 strlcat(buf, "|VV_MD", sizeof(buf));
3031 if (vp->v_vflag & VV_FORCEINSMQ)
3032 strlcat(buf, "|VV_FORCEINSMQ", sizeof(buf));
3033 flags = vp->v_vflag & ~(VV_ROOT | VV_ISTTY | VV_NOSYNC | VV_ETERNALDEV |
3034 VV_CACHEDLABEL | VV_TEXT | VV_COPYONWRITE | VV_SYSTEM | VV_PROCDEP |
3035 VV_NOKNOTE | VV_DELETED | VV_MD | VV_FORCEINSMQ);
3036 if (flags != 0) {
3037 snprintf(buf2, sizeof(buf2), "|VV(0x%lx)", flags);
3038 strlcat(buf, buf2, sizeof(buf));
3039 }
3040 if (vp->v_iflag & VI_MOUNT)
3041 strlcat(buf, "|VI_MOUNT", sizeof(buf));
3042 if (vp->v_iflag & VI_AGE)
3043 strlcat(buf, "|VI_AGE", sizeof(buf));
3044 if (vp->v_iflag & VI_DOOMED)
3045 strlcat(buf, "|VI_DOOMED", sizeof(buf));
3046 if (vp->v_iflag & VI_FREE)
3047 strlcat(buf, "|VI_FREE", sizeof(buf));
3048 if (vp->v_iflag & VI_ACTIVE)
3049 strlcat(buf, "|VI_ACTIVE", sizeof(buf));
3050 if (vp->v_iflag & VI_DOINGINACT)
3051 strlcat(buf, "|VI_DOINGINACT", sizeof(buf));
3052 if (vp->v_iflag & VI_OWEINACT)
3053 strlcat(buf, "|VI_OWEINACT", sizeof(buf));
3054 flags = vp->v_iflag & ~(VI_MOUNT | VI_AGE | VI_DOOMED | VI_FREE |
3055 VI_ACTIVE | VI_DOINGINACT | VI_OWEINACT);
3056 if (flags != 0) {
3057 snprintf(buf2, sizeof(buf2), "|VI(0x%lx)", flags);
3058 strlcat(buf, buf2, sizeof(buf));
3059 }
3060 printf(" flags (%s)\n", buf + 1);
3061 if (mtx_owned(VI_MTX(vp)))
3062 printf(" VI_LOCKed");
3063 if (vp->v_object != NULL)
3064 printf(" v_object %p ref %d pages %d "
3065 "cleanbuf %d dirtybuf %d\n",
3066 vp->v_object, vp->v_object->ref_count,
3067 vp->v_object->resident_page_count,
3068 vp->v_bufobj.bo_dirty.bv_cnt,
3069 vp->v_bufobj.bo_clean.bv_cnt);
3070 printf(" ");
3071 lockmgr_printinfo(vp->v_vnlock);
3072 if (vp->v_data != NULL)
3073 VOP_PRINT(vp);
3074 }
3075
3076 #ifdef DDB
3077 /*
3078 * List all of the locked vnodes in the system.
3079 * Called when debugging the kernel.
3080 */
3081 DB_SHOW_COMMAND(lockedvnods, lockedvnodes)
3082 {
3083 struct mount *mp, *nmp;
3084 struct vnode *vp;
3085
3086 /*
3087 * Note: because this is DDB, we can't obey the locking semantics
3088 * for these structures, which means we could catch an inconsistent
3089 * state and dereference a nasty pointer. Not much to be done
3090 * about that.
3091 */
3092 db_printf("Locked vnodes\n");
3093 for (mp = TAILQ_FIRST(&mountlist); mp != NULL; mp = nmp) {
3094 nmp = TAILQ_NEXT(mp, mnt_list);
3095 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) {
3096 if (vp->v_type != VMARKER &&
3097 VOP_ISLOCKED(vp))
3098 vprint("", vp);
3099 }
3100 nmp = TAILQ_NEXT(mp, mnt_list);
3101 }
3102 }
3103
3104 /*
3105 * Show details about the given vnode.
3106 */
3107 DB_SHOW_COMMAND(vnode, db_show_vnode)
3108 {
3109 struct vnode *vp;
3110
3111 if (!have_addr)
3112 return;
3113 vp = (struct vnode *)addr;
3114 vn_printf(vp, "vnode ");
3115 }
3116
3117 /*
3118 * Show details about the given mount point.
3119 */
3120 DB_SHOW_COMMAND(mount, db_show_mount)
3121 {
3122 struct mount *mp;
3123 struct vfsopt *opt;
3124 struct statfs *sp;
3125 struct vnode *vp;
3126 char buf[512];
3127 uint64_t mflags;
3128 u_int flags;
3129
3130 if (!have_addr) {
3131 /* No address given, print short info about all mount points. */
3132 TAILQ_FOREACH(mp, &mountlist, mnt_list) {
3133 db_printf("%p %s on %s (%s)\n", mp,
3134 mp->mnt_stat.f_mntfromname,
3135 mp->mnt_stat.f_mntonname,
3136 mp->mnt_stat.f_fstypename);
3137 if (db_pager_quit)
3138 break;
3139 }
3140 db_printf("\nMore info: show mount <addr>\n");
3141 return;
3142 }
3143
3144 mp = (struct mount *)addr;
3145 db_printf("%p %s on %s (%s)\n", mp, mp->mnt_stat.f_mntfromname,
3146 mp->mnt_stat.f_mntonname, mp->mnt_stat.f_fstypename);
3147
3148 buf[0] = '\0';
3149 mflags = mp->mnt_flag;
3150 #define MNT_FLAG(flag) do { \
3151 if (mflags & (flag)) { \
3152 if (buf[0] != '\0') \
3153 strlcat(buf, ", ", sizeof(buf)); \
3154 strlcat(buf, (#flag) + 4, sizeof(buf)); \
3155 mflags &= ~(flag); \
3156 } \
3157 } while (0)
3158 MNT_FLAG(MNT_RDONLY);
3159 MNT_FLAG(MNT_SYNCHRONOUS);
3160 MNT_FLAG(MNT_NOEXEC);
3161 MNT_FLAG(MNT_NOSUID);
3162 MNT_FLAG(MNT_NFS4ACLS);
3163 MNT_FLAG(MNT_UNION);
3164 MNT_FLAG(MNT_ASYNC);
3165 MNT_FLAG(MNT_SUIDDIR);
3166 MNT_FLAG(MNT_SOFTDEP);
3167 MNT_FLAG(MNT_NOSYMFOLLOW);
3168 MNT_FLAG(MNT_GJOURNAL);
3169 MNT_FLAG(MNT_MULTILABEL);
3170 MNT_FLAG(MNT_ACLS);
3171 MNT_FLAG(MNT_NOATIME);
3172 MNT_FLAG(MNT_NOCLUSTERR);
3173 MNT_FLAG(MNT_NOCLUSTERW);
3174 MNT_FLAG(MNT_SUJ);
3175 MNT_FLAG(MNT_EXRDONLY);
3176 MNT_FLAG(MNT_EXPORTED);
3177 MNT_FLAG(MNT_DEFEXPORTED);
3178 MNT_FLAG(MNT_EXPORTANON);
3179 MNT_FLAG(MNT_EXKERB);
3180 MNT_FLAG(MNT_EXPUBLIC);
3181 MNT_FLAG(MNT_LOCAL);
3182 MNT_FLAG(MNT_QUOTA);
3183 MNT_FLAG(MNT_ROOTFS);
3184 MNT_FLAG(MNT_USER);
3185 MNT_FLAG(MNT_IGNORE);
3186 MNT_FLAG(MNT_UPDATE);
3187 MNT_FLAG(MNT_DELEXPORT);
3188 MNT_FLAG(MNT_RELOAD);
3189 MNT_FLAG(MNT_FORCE);
3190 MNT_FLAG(MNT_SNAPSHOT);
3191 MNT_FLAG(MNT_BYFSID);
3192 #undef MNT_FLAG
3193 if (mflags != 0) {
3194 if (buf[0] != '\0')
3195 strlcat(buf, ", ", sizeof(buf));
3196 snprintf(buf + strlen(buf), sizeof(buf) - strlen(buf),
3197 "0x%016jx", mflags);
3198 }
3199 db_printf(" mnt_flag = %s\n", buf);
3200
3201 buf[0] = '\0';
3202 flags = mp->mnt_kern_flag;
3203 #define MNT_KERN_FLAG(flag) do { \
3204 if (flags & (flag)) { \
3205 if (buf[0] != '\0') \
3206 strlcat(buf, ", ", sizeof(buf)); \
3207 strlcat(buf, (#flag) + 5, sizeof(buf)); \
3208 flags &= ~(flag); \
3209 } \
3210 } while (0)
3211 MNT_KERN_FLAG(MNTK_UNMOUNTF);
3212 MNT_KERN_FLAG(MNTK_ASYNC);
3213 MNT_KERN_FLAG(MNTK_SOFTDEP);
3214 MNT_KERN_FLAG(MNTK_NOINSMNTQ);
3215 MNT_KERN_FLAG(MNTK_DRAINING);
3216 MNT_KERN_FLAG(MNTK_REFEXPIRE);
3217 MNT_KERN_FLAG(MNTK_EXTENDED_SHARED);
3218 MNT_KERN_FLAG(MNTK_SHARED_WRITES);
3219 MNT_KERN_FLAG(MNTK_NO_IOPF);
3220 MNT_KERN_FLAG(MNTK_VGONE_UPPER);
3221 MNT_KERN_FLAG(MNTK_VGONE_WAITER);
3222 MNT_KERN_FLAG(MNTK_LOOKUP_EXCL_DOTDOT);
3223 MNT_KERN_FLAG(MNTK_MARKER);
3224 MNT_KERN_FLAG(MNTK_NOASYNC);
3225 MNT_KERN_FLAG(MNTK_UNMOUNT);
3226 MNT_KERN_FLAG(MNTK_MWAIT);
3227 MNT_KERN_FLAG(MNTK_SUSPEND);
3228 MNT_KERN_FLAG(MNTK_SUSPEND2);
3229 MNT_KERN_FLAG(MNTK_SUSPENDED);
3230 MNT_KERN_FLAG(MNTK_MPSAFE);
3231 MNT_KERN_FLAG(MNTK_LOOKUP_SHARED);
3232 MNT_KERN_FLAG(MNTK_NOKNOTE);
3233 #undef MNT_KERN_FLAG
3234 if (flags != 0) {
3235 if (buf[0] != '\0')
3236 strlcat(buf, ", ", sizeof(buf));
3237 snprintf(buf + strlen(buf), sizeof(buf) - strlen(buf),
3238 "0x%08x", flags);
3239 }
3240 db_printf(" mnt_kern_flag = %s\n", buf);
3241
3242 db_printf(" mnt_opt = ");
3243 opt = TAILQ_FIRST(mp->mnt_opt);
3244 if (opt != NULL) {
3245 db_printf("%s", opt->name);
3246 opt = TAILQ_NEXT(opt, link);
3247 while (opt != NULL) {
3248 db_printf(", %s", opt->name);
3249 opt = TAILQ_NEXT(opt, link);
3250 }
3251 }
3252 db_printf("\n");
3253
3254 sp = &mp->mnt_stat;
3255 db_printf(" mnt_stat = { version=%u type=%u flags=0x%016jx "
3256 "bsize=%ju iosize=%ju blocks=%ju bfree=%ju bavail=%jd files=%ju "
3257 "ffree=%jd syncwrites=%ju asyncwrites=%ju syncreads=%ju "
3258 "asyncreads=%ju namemax=%u owner=%u fsid=[%d, %d] }\n",
3259 (u_int)sp->f_version, (u_int)sp->f_type, (uintmax_t)sp->f_flags,
3260 (uintmax_t)sp->f_bsize, (uintmax_t)sp->f_iosize,
3261 (uintmax_t)sp->f_blocks, (uintmax_t)sp->f_bfree,
3262 (intmax_t)sp->f_bavail, (uintmax_t)sp->f_files,
3263 (intmax_t)sp->f_ffree, (uintmax_t)sp->f_syncwrites,
3264 (uintmax_t)sp->f_asyncwrites, (uintmax_t)sp->f_syncreads,
3265 (uintmax_t)sp->f_asyncreads, (u_int)sp->f_namemax,
3266 (u_int)sp->f_owner, (int)sp->f_fsid.val[0], (int)sp->f_fsid.val[1]);
3267
3268 db_printf(" mnt_cred = { uid=%u ruid=%u",
3269 (u_int)mp->mnt_cred->cr_uid, (u_int)mp->mnt_cred->cr_ruid);
3270 if (jailed(mp->mnt_cred))
3271 db_printf(", jail=%d", mp->mnt_cred->cr_prison->pr_id);
3272 db_printf(" }\n");
3273 db_printf(" mnt_ref = %d\n", mp->mnt_ref);
3274 db_printf(" mnt_gen = %d\n", mp->mnt_gen);
3275 db_printf(" mnt_nvnodelistsize = %d\n", mp->mnt_nvnodelistsize);
3276 db_printf(" mnt_activevnodelistsize = %d\n",
3277 mp->mnt_activevnodelistsize);
3278 db_printf(" mnt_writeopcount = %d\n", mp->mnt_writeopcount);
3279 db_printf(" mnt_maxsymlinklen = %d\n", mp->mnt_maxsymlinklen);
3280 db_printf(" mnt_iosize_max = %d\n", mp->mnt_iosize_max);
3281 db_printf(" mnt_hashseed = %u\n", mp->mnt_hashseed);
3282 db_printf(" mnt_lockref = %d\n", mp->mnt_lockref);
3283 db_printf(" mnt_secondary_writes = %d\n", mp->mnt_secondary_writes);
3284 db_printf(" mnt_secondary_accwrites = %d\n",
3285 mp->mnt_secondary_accwrites);
3286 db_printf(" mnt_gjprovider = %s\n",
3287 mp->mnt_gjprovider != NULL ? mp->mnt_gjprovider : "NULL");
3288
3289 db_printf("\n\nList of active vnodes\n");
3290 TAILQ_FOREACH(vp, &mp->mnt_activevnodelist, v_actfreelist) {
3291 if (vp->v_type != VMARKER) {
3292 vn_printf(vp, "vnode ");
3293 if (db_pager_quit)
3294 break;
3295 }
3296 }
3297 db_printf("\n\nList of inactive vnodes\n");
3298 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) {
3299 if (vp->v_type != VMARKER && (vp->v_iflag & VI_ACTIVE) == 0) {
3300 vn_printf(vp, "vnode ");
3301 if (db_pager_quit)
3302 break;
3303 }
3304 }
3305 }
3306 #endif /* DDB */
3307
3308 /*
3309 * Fill in a struct xvfsconf based on a struct vfsconf.
3310 */
3311 static int
3312 vfsconf2x(struct sysctl_req *req, struct vfsconf *vfsp)
3313 {
3314 struct xvfsconf xvfsp;
3315
3316 bzero(&xvfsp, sizeof(xvfsp));
3317 strcpy(xvfsp.vfc_name, vfsp->vfc_name);
3318 xvfsp.vfc_typenum = vfsp->vfc_typenum;
3319 xvfsp.vfc_refcount = vfsp->vfc_refcount;
3320 xvfsp.vfc_flags = vfsp->vfc_flags;
3321 /*
3322 * These are unused in userland, we keep them
3323 * to not break binary compatibility.
3324 */
3325 xvfsp.vfc_vfsops = NULL;
3326 xvfsp.vfc_next = NULL;
3327 return (SYSCTL_OUT(req, &xvfsp, sizeof(xvfsp)));
3328 }
3329
3330 #ifdef COMPAT_FREEBSD32
3331 struct xvfsconf32 {
3332 uint32_t vfc_vfsops;
3333 char vfc_name[MFSNAMELEN];
3334 int32_t vfc_typenum;
3335 int32_t vfc_refcount;
3336 int32_t vfc_flags;
3337 uint32_t vfc_next;
3338 };
3339
3340 static int
3341 vfsconf2x32(struct sysctl_req *req, struct vfsconf *vfsp)
3342 {
3343 struct xvfsconf32 xvfsp;
3344
3345 strcpy(xvfsp.vfc_name, vfsp->vfc_name);
3346 xvfsp.vfc_typenum = vfsp->vfc_typenum;
3347 xvfsp.vfc_refcount = vfsp->vfc_refcount;
3348 xvfsp.vfc_flags = vfsp->vfc_flags;
3349 xvfsp.vfc_vfsops = 0;
3350 xvfsp.vfc_next = 0;
3351 return (SYSCTL_OUT(req, &xvfsp, sizeof(xvfsp)));
3352 }
3353 #endif
3354
3355 /*
3356 * Top level filesystem related information gathering.
3357 */
3358 static int
3359 sysctl_vfs_conflist(SYSCTL_HANDLER_ARGS)
3360 {
3361 struct vfsconf *vfsp;
3362 int error;
3363
3364 error = 0;
3365 TAILQ_FOREACH(vfsp, &vfsconf, vfc_list) {
3366 #ifdef COMPAT_FREEBSD32
3367 if (req->flags & SCTL_MASK32)
3368 error = vfsconf2x32(req, vfsp);
3369 else
3370 #endif
3371 error = vfsconf2x(req, vfsp);
3372 if (error)
3373 break;
3374 }
3375 return (error);
3376 }
3377
3378 SYSCTL_PROC(_vfs, OID_AUTO, conflist, CTLTYPE_OPAQUE | CTLFLAG_RD,
3379 NULL, 0, sysctl_vfs_conflist,
3380 "S,xvfsconf", "List of all configured filesystems");
3381
3382 #ifndef BURN_BRIDGES
3383 static int sysctl_ovfs_conf(SYSCTL_HANDLER_ARGS);
3384
3385 static int
3386 vfs_sysctl(SYSCTL_HANDLER_ARGS)
3387 {
3388 int *name = (int *)arg1 - 1; /* XXX */
3389 u_int namelen = arg2 + 1; /* XXX */
3390 struct vfsconf *vfsp;
3391
3392 printf("WARNING: userland calling deprecated sysctl, "
3393 "please rebuild world\n");
3394
3395 #if 1 || defined(COMPAT_PRELITE2)
3396 /* Resolve ambiguity between VFS_VFSCONF and VFS_GENERIC. */
3397 if (namelen == 1)
3398 return (sysctl_ovfs_conf(oidp, arg1, arg2, req));
3399 #endif
3400
3401 switch (name[1]) {
3402 case VFS_MAXTYPENUM:
3403 if (namelen != 2)
3404 return (ENOTDIR);
3405 return (SYSCTL_OUT(req, &maxvfsconf, sizeof(int)));
3406 case VFS_CONF:
3407 if (namelen != 3)
3408 return (ENOTDIR); /* overloaded */
3409 TAILQ_FOREACH(vfsp, &vfsconf, vfc_list)
3410 if (vfsp->vfc_typenum == name[2])
3411 break;
3412 if (vfsp == NULL)
3413 return (EOPNOTSUPP);
3414 #ifdef COMPAT_FREEBSD32
3415 if (req->flags & SCTL_MASK32)
3416 return (vfsconf2x32(req, vfsp));
3417 else
3418 #endif
3419 return (vfsconf2x(req, vfsp));
3420 }
3421 return (EOPNOTSUPP);
3422 }
3423
3424 static SYSCTL_NODE(_vfs, VFS_GENERIC, generic, CTLFLAG_RD | CTLFLAG_SKIP,
3425 vfs_sysctl, "Generic filesystem");
3426
3427 #if 1 || defined(COMPAT_PRELITE2)
3428
3429 static int
3430 sysctl_ovfs_conf(SYSCTL_HANDLER_ARGS)
3431 {
3432 int error;
3433 struct vfsconf *vfsp;
3434 struct ovfsconf ovfs;
3435
3436 TAILQ_FOREACH(vfsp, &vfsconf, vfc_list) {
3437 bzero(&ovfs, sizeof(ovfs));
3438 ovfs.vfc_vfsops = vfsp->vfc_vfsops; /* XXX used as flag */
3439 strcpy(ovfs.vfc_name, vfsp->vfc_name);
3440 ovfs.vfc_index = vfsp->vfc_typenum;
3441 ovfs.vfc_refcount = vfsp->vfc_refcount;
3442 ovfs.vfc_flags = vfsp->vfc_flags;
3443 error = SYSCTL_OUT(req, &ovfs, sizeof ovfs);
3444 if (error)
3445 return error;
3446 }
3447 return 0;
3448 }
3449
3450 #endif /* 1 || COMPAT_PRELITE2 */
3451 #endif /* !BURN_BRIDGES */
3452
3453 #define KINFO_VNODESLOP 10
3454 #ifdef notyet
3455 /*
3456 * Dump vnode list (via sysctl).
3457 */
3458 /* ARGSUSED */
3459 static int
3460 sysctl_vnode(SYSCTL_HANDLER_ARGS)
3461 {
3462 struct xvnode *xvn;
3463 struct mount *mp;
3464 struct vnode *vp;
3465 int error, len, n;
3466
3467 /*
3468 * Stale numvnodes access is not fatal here.
3469 */
3470 req->lock = 0;
3471 len = (numvnodes + KINFO_VNODESLOP) * sizeof *xvn;
3472 if (!req->oldptr)
3473 /* Make an estimate */
3474 return (SYSCTL_OUT(req, 0, len));
3475
3476 error = sysctl_wire_old_buffer(req, 0);
3477 if (error != 0)
3478 return (error);
3479 xvn = malloc(len, M_TEMP, M_ZERO | M_WAITOK);
3480 n = 0;
3481 mtx_lock(&mountlist_mtx);
3482 TAILQ_FOREACH(mp, &mountlist, mnt_list) {
3483 if (vfs_busy(mp, MBF_NOWAIT | MBF_MNTLSTLOCK))
3484 continue;
3485 MNT_ILOCK(mp);
3486 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) {
3487 if (n == len)
3488 break;
3489 vref(vp);
3490 xvn[n].xv_size = sizeof *xvn;
3491 xvn[n].xv_vnode = vp;
3492 xvn[n].xv_id = 0; /* XXX compat */
3493 #define XV_COPY(field) xvn[n].xv_##field = vp->v_##field
3494 XV_COPY(usecount);
3495 XV_COPY(writecount);
3496 XV_COPY(holdcnt);
3497 XV_COPY(mount);
3498 XV_COPY(numoutput);
3499 XV_COPY(type);
3500 #undef XV_COPY
3501 xvn[n].xv_flag = vp->v_vflag;
3502
3503 switch (vp->v_type) {
3504 case VREG:
3505 case VDIR:
3506 case VLNK:
3507 break;
3508 case VBLK:
3509 case VCHR:
3510 if (vp->v_rdev == NULL) {
3511 vrele(vp);
3512 continue;
3513 }
3514 xvn[n].xv_dev = dev2udev(vp->v_rdev);
3515 break;
3516 case VSOCK:
3517 xvn[n].xv_socket = vp->v_socket;
3518 break;
3519 case VFIFO:
3520 xvn[n].xv_fifo = vp->v_fifoinfo;
3521 break;
3522 case VNON:
3523 case VBAD:
3524 default:
3525 /* shouldn't happen? */
3526 vrele(vp);
3527 continue;
3528 }
3529 vrele(vp);
3530 ++n;
3531 }
3532 MNT_IUNLOCK(mp);
3533 mtx_lock(&mountlist_mtx);
3534 vfs_unbusy(mp);
3535 if (n == len)
3536 break;
3537 }
3538 mtx_unlock(&mountlist_mtx);
3539
3540 error = SYSCTL_OUT(req, xvn, n * sizeof *xvn);
3541 free(xvn, M_TEMP);
3542 return (error);
3543 }
3544
3545 SYSCTL_PROC(_kern, KERN_VNODE, vnode, CTLTYPE_OPAQUE|CTLFLAG_RD,
3546 0, 0, sysctl_vnode, "S,xvnode", "");
3547 #endif
3548
3549 /*
3550 * Unmount all filesystems. The list is traversed in reverse order
3551 * of mounting to avoid dependencies.
3552 */
3553 void
3554 vfs_unmountall(void)
3555 {
3556 struct mount *mp;
3557 struct thread *td;
3558 int error;
3559
3560 CTR1(KTR_VFS, "%s: unmounting all filesystems", __func__);
3561 td = curthread;
3562
3563 /*
3564 * Since this only runs when rebooting, it is not interlocked.
3565 */
3566 while(!TAILQ_EMPTY(&mountlist)) {
3567 mp = TAILQ_LAST(&mountlist, mntlist);
3568 error = dounmount(mp, MNT_FORCE, td);
3569 if (error) {
3570 TAILQ_REMOVE(&mountlist, mp, mnt_list);
3571 /*
3572 * XXX: Due to the way in which we mount the root
3573 * file system off of devfs, devfs will generate a
3574 * "busy" warning when we try to unmount it before
3575 * the root. Don't print a warning as a result in
3576 * order to avoid false positive errors that may
3577 * cause needless upset.
3578 */
3579 if (strcmp(mp->mnt_vfc->vfc_name, "devfs") != 0) {
3580 printf("unmount of %s failed (",
3581 mp->mnt_stat.f_mntonname);
3582 if (error == EBUSY)
3583 printf("BUSY)\n");
3584 else
3585 printf("%d)\n", error);
3586 }
3587 } else {
3588 /* The unmount has removed mp from the mountlist */
3589 }
3590 }
3591 }
3592
3593 /*
3594 * perform msync on all vnodes under a mount point
3595 * the mount point must be locked.
3596 */
3597 void
3598 vfs_msync(struct mount *mp, int flags)
3599 {
3600 struct vnode *vp, *mvp;
3601 struct vm_object *obj;
3602
3603 CTR2(KTR_VFS, "%s: mp %p", __func__, mp);
3604 MNT_VNODE_FOREACH_ACTIVE(vp, mp, mvp) {
3605 obj = vp->v_object;
3606 if (obj != NULL && (obj->flags & OBJ_MIGHTBEDIRTY) != 0 &&
3607 (flags == MNT_WAIT || VOP_ISLOCKED(vp) == 0)) {
3608 if (!vget(vp,
3609 LK_EXCLUSIVE | LK_RETRY | LK_INTERLOCK,
3610 curthread)) {
3611 if (vp->v_vflag & VV_NOSYNC) { /* unlinked */
3612 vput(vp);
3613 continue;
3614 }
3615
3616 obj = vp->v_object;
3617 if (obj != NULL) {
3618 VM_OBJECT_LOCK(obj);
3619 vm_object_page_clean(obj, 0, 0,
3620 flags == MNT_WAIT ?
3621 OBJPC_SYNC : OBJPC_NOSYNC);
3622 VM_OBJECT_UNLOCK(obj);
3623 }
3624 vput(vp);
3625 }
3626 } else
3627 VI_UNLOCK(vp);
3628 }
3629 }
3630
3631 static void
3632 destroy_vpollinfo_free(struct vpollinfo *vi)
3633 {
3634
3635 knlist_destroy(&vi->vpi_selinfo.si_note);
3636 mtx_destroy(&vi->vpi_lock);
3637 uma_zfree(vnodepoll_zone, vi);
3638 }
3639
3640 static void
3641 destroy_vpollinfo(struct vpollinfo *vi)
3642 {
3643
3644 knlist_clear(&vi->vpi_selinfo.si_note, 1);
3645 seldrain(&vi->vpi_selinfo);
3646 destroy_vpollinfo_free(vi);
3647 }
3648
3649 /*
3650 * Initalize per-vnode helper structure to hold poll-related state.
3651 */
3652 void
3653 v_addpollinfo(struct vnode *vp)
3654 {
3655 struct vpollinfo *vi;
3656
3657 if (vp->v_pollinfo != NULL)
3658 return;
3659 vi = uma_zalloc(vnodepoll_zone, M_WAITOK);
3660 mtx_init(&vi->vpi_lock, "vnode pollinfo", NULL, MTX_DEF);
3661 knlist_init(&vi->vpi_selinfo.si_note, vp, vfs_knllock,
3662 vfs_knlunlock, vfs_knl_assert_locked, vfs_knl_assert_unlocked);
3663 VI_LOCK(vp);
3664 if (vp->v_pollinfo != NULL) {
3665 VI_UNLOCK(vp);
3666 destroy_vpollinfo_free(vi);
3667 return;
3668 }
3669 vp->v_pollinfo = vi;
3670 VI_UNLOCK(vp);
3671 }
3672
3673 /*
3674 * Record a process's interest in events which might happen to
3675 * a vnode. Because poll uses the historic select-style interface
3676 * internally, this routine serves as both the ``check for any
3677 * pending events'' and the ``record my interest in future events''
3678 * functions. (These are done together, while the lock is held,
3679 * to avoid race conditions.)
3680 */
3681 int
3682 vn_pollrecord(struct vnode *vp, struct thread *td, int events)
3683 {
3684
3685 v_addpollinfo(vp);
3686 mtx_lock(&vp->v_pollinfo->vpi_lock);
3687 if (vp->v_pollinfo->vpi_revents & events) {
3688 /*
3689 * This leaves events we are not interested
3690 * in available for the other process which
3691 * which presumably had requested them
3692 * (otherwise they would never have been
3693 * recorded).
3694 */
3695 events &= vp->v_pollinfo->vpi_revents;
3696 vp->v_pollinfo->vpi_revents &= ~events;
3697
3698 mtx_unlock(&vp->v_pollinfo->vpi_lock);
3699 return (events);
3700 }
3701 vp->v_pollinfo->vpi_events |= events;
3702 selrecord(td, &vp->v_pollinfo->vpi_selinfo);
3703 mtx_unlock(&vp->v_pollinfo->vpi_lock);
3704 return (0);
3705 }
3706
3707 /*
3708 * Routine to create and manage a filesystem syncer vnode.
3709 */
3710 #define sync_close ((int (*)(struct vop_close_args *))nullop)
3711 static int sync_fsync(struct vop_fsync_args *);
3712 static int sync_inactive(struct vop_inactive_args *);
3713 static int sync_reclaim(struct vop_reclaim_args *);
3714
3715 static struct vop_vector sync_vnodeops = {
3716 .vop_bypass = VOP_EOPNOTSUPP,
3717 .vop_close = sync_close, /* close */
3718 .vop_fsync = sync_fsync, /* fsync */
3719 .vop_inactive = sync_inactive, /* inactive */
3720 .vop_reclaim = sync_reclaim, /* reclaim */
3721 .vop_lock1 = vop_stdlock, /* lock */
3722 .vop_unlock = vop_stdunlock, /* unlock */
3723 .vop_islocked = vop_stdislocked, /* islocked */
3724 };
3725
3726 /*
3727 * Create a new filesystem syncer vnode for the specified mount point.
3728 */
3729 void
3730 vfs_allocate_syncvnode(struct mount *mp)
3731 {
3732 struct vnode *vp;
3733 struct bufobj *bo;
3734 static long start, incr, next;
3735 int error;
3736
3737 /* Allocate a new vnode */
3738 error = getnewvnode("syncer", mp, &sync_vnodeops, &vp);
3739 if (error != 0)
3740 panic("vfs_allocate_syncvnode: getnewvnode() failed");
3741 vp->v_type = VNON;
3742 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
3743 vp->v_vflag |= VV_FORCEINSMQ;
3744 error = insmntque(vp, mp);
3745 if (error != 0)
3746 panic("vfs_allocate_syncvnode: insmntque() failed");
3747 vp->v_vflag &= ~VV_FORCEINSMQ;
3748 VOP_UNLOCK(vp, 0);
3749 /*
3750 * Place the vnode onto the syncer worklist. We attempt to
3751 * scatter them about on the list so that they will go off
3752 * at evenly distributed times even if all the filesystems
3753 * are mounted at once.
3754 */
3755 next += incr;
3756 if (next == 0 || next > syncer_maxdelay) {
3757 start /= 2;
3758 incr /= 2;
3759 if (start == 0) {
3760 start = syncer_maxdelay / 2;
3761 incr = syncer_maxdelay;
3762 }
3763 next = start;
3764 }
3765 bo = &vp->v_bufobj;
3766 BO_LOCK(bo);
3767 vn_syncer_add_to_worklist(bo, syncdelay > 0 ? next % syncdelay : 0);
3768 /* XXX - vn_syncer_add_to_worklist() also grabs and drops sync_mtx. */
3769 mtx_lock(&sync_mtx);
3770 sync_vnode_count++;
3771 if (mp->mnt_syncer == NULL) {
3772 mp->mnt_syncer = vp;
3773 vp = NULL;
3774 }
3775 mtx_unlock(&sync_mtx);
3776 BO_UNLOCK(bo);
3777 if (vp != NULL) {
3778 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
3779 vgone(vp);
3780 vput(vp);
3781 }
3782 }
3783
3784 void
3785 vfs_deallocate_syncvnode(struct mount *mp)
3786 {
3787 struct vnode *vp;
3788
3789 mtx_lock(&sync_mtx);
3790 vp = mp->mnt_syncer;
3791 if (vp != NULL)
3792 mp->mnt_syncer = NULL;
3793 mtx_unlock(&sync_mtx);
3794 if (vp != NULL)
3795 vrele(vp);
3796 }
3797
3798 /*
3799 * Do a lazy sync of the filesystem.
3800 */
3801 static int
3802 sync_fsync(struct vop_fsync_args *ap)
3803 {
3804 struct vnode *syncvp = ap->a_vp;
3805 struct mount *mp = syncvp->v_mount;
3806 int error, save;
3807 struct bufobj *bo;
3808
3809 /*
3810 * We only need to do something if this is a lazy evaluation.
3811 */
3812 if (ap->a_waitfor != MNT_LAZY)
3813 return (0);
3814
3815 /*
3816 * Move ourselves to the back of the sync list.
3817 */
3818 bo = &syncvp->v_bufobj;
3819 BO_LOCK(bo);
3820 vn_syncer_add_to_worklist(bo, syncdelay);
3821 BO_UNLOCK(bo);
3822
3823 /*
3824 * Walk the list of vnodes pushing all that are dirty and
3825 * not already on the sync list.
3826 */
3827 if (vfs_busy(mp, MBF_NOWAIT) != 0)
3828 return (0);
3829 if (vn_start_write(NULL, &mp, V_NOWAIT) != 0) {
3830 vfs_unbusy(mp);
3831 return (0);
3832 }
3833 save = curthread_pflags_set(TDP_SYNCIO);
3834 vfs_msync(mp, MNT_NOWAIT);
3835 error = VFS_SYNC(mp, MNT_LAZY);
3836 curthread_pflags_restore(save);
3837 vn_finished_write(mp);
3838 vfs_unbusy(mp);
3839 return (error);
3840 }
3841
3842 /*
3843 * The syncer vnode is no referenced.
3844 */
3845 static int
3846 sync_inactive(struct vop_inactive_args *ap)
3847 {
3848
3849 vgone(ap->a_vp);
3850 return (0);
3851 }
3852
3853 /*
3854 * The syncer vnode is no longer needed and is being decommissioned.
3855 *
3856 * Modifications to the worklist must be protected by sync_mtx.
3857 */
3858 static int
3859 sync_reclaim(struct vop_reclaim_args *ap)
3860 {
3861 struct vnode *vp = ap->a_vp;
3862 struct bufobj *bo;
3863
3864 bo = &vp->v_bufobj;
3865 BO_LOCK(bo);
3866 mtx_lock(&sync_mtx);
3867 if (vp->v_mount->mnt_syncer == vp)
3868 vp->v_mount->mnt_syncer = NULL;
3869 if (bo->bo_flag & BO_ONWORKLST) {
3870 LIST_REMOVE(bo, bo_synclist);
3871 syncer_worklist_len--;
3872 sync_vnode_count--;
3873 bo->bo_flag &= ~BO_ONWORKLST;
3874 }
3875 mtx_unlock(&sync_mtx);
3876 BO_UNLOCK(bo);
3877
3878 return (0);
3879 }
3880
3881 /*
3882 * Check if vnode represents a disk device
3883 */
3884 int
3885 vn_isdisk(struct vnode *vp, int *errp)
3886 {
3887 int error;
3888
3889 error = 0;
3890 dev_lock();
3891 if (vp->v_type != VCHR)
3892 error = ENOTBLK;
3893 else if (vp->v_rdev == NULL)
3894 error = ENXIO;
3895 else if (vp->v_rdev->si_devsw == NULL)
3896 error = ENXIO;
3897 else if (!(vp->v_rdev->si_devsw->d_flags & D_DISK))
3898 error = ENOTBLK;
3899 dev_unlock();
3900 if (errp != NULL)
3901 *errp = error;
3902 return (error == 0);
3903 }
3904
3905 /*
3906 * Common filesystem object access control check routine. Accepts a
3907 * vnode's type, "mode", uid and gid, requested access mode, credentials,
3908 * and optional call-by-reference privused argument allowing vaccess()
3909 * to indicate to the caller whether privilege was used to satisfy the
3910 * request (obsoleted). Returns 0 on success, or an errno on failure.
3911 */
3912 int
3913 vaccess(enum vtype type, mode_t file_mode, uid_t file_uid, gid_t file_gid,
3914 accmode_t accmode, struct ucred *cred, int *privused)
3915 {
3916 accmode_t dac_granted;
3917 accmode_t priv_granted;
3918
3919 KASSERT((accmode & ~(VEXEC | VWRITE | VREAD | VADMIN | VAPPEND)) == 0,
3920 ("invalid bit in accmode"));
3921 KASSERT((accmode & VAPPEND) == 0 || (accmode & VWRITE),
3922 ("VAPPEND without VWRITE"));
3923
3924 /*
3925 * Look for a normal, non-privileged way to access the file/directory
3926 * as requested. If it exists, go with that.
3927 */
3928
3929 if (privused != NULL)
3930 *privused = 0;
3931
3932 dac_granted = 0;
3933
3934 /* Check the owner. */
3935 if (cred->cr_uid == file_uid) {
3936 dac_granted |= VADMIN;
3937 if (file_mode & S_IXUSR)
3938 dac_granted |= VEXEC;
3939 if (file_mode & S_IRUSR)
3940 dac_granted |= VREAD;
3941 if (file_mode & S_IWUSR)
3942 dac_granted |= (VWRITE | VAPPEND);
3943
3944 if ((accmode & dac_granted) == accmode)
3945 return (0);
3946
3947 goto privcheck;
3948 }
3949
3950 /* Otherwise, check the groups (first match) */
3951 if (groupmember(file_gid, cred)) {
3952 if (file_mode & S_IXGRP)
3953 dac_granted |= VEXEC;
3954 if (file_mode & S_IRGRP)
3955 dac_granted |= VREAD;
3956 if (file_mode & S_IWGRP)
3957 dac_granted |= (VWRITE | VAPPEND);
3958
3959 if ((accmode & dac_granted) == accmode)
3960 return (0);
3961
3962 goto privcheck;
3963 }
3964
3965 /* Otherwise, check everyone else. */
3966 if (file_mode & S_IXOTH)
3967 dac_granted |= VEXEC;
3968 if (file_mode & S_IROTH)
3969 dac_granted |= VREAD;
3970 if (file_mode & S_IWOTH)
3971 dac_granted |= (VWRITE | VAPPEND);
3972 if ((accmode & dac_granted) == accmode)
3973 return (0);
3974
3975 privcheck:
3976 /*
3977 * Build a privilege mask to determine if the set of privileges
3978 * satisfies the requirements when combined with the granted mask
3979 * from above. For each privilege, if the privilege is required,
3980 * bitwise or the request type onto the priv_granted mask.
3981 */
3982 priv_granted = 0;
3983
3984 if (type == VDIR) {
3985 /*
3986 * For directories, use PRIV_VFS_LOOKUP to satisfy VEXEC
3987 * requests, instead of PRIV_VFS_EXEC.
3988 */
3989 if ((accmode & VEXEC) && ((dac_granted & VEXEC) == 0) &&
3990 !priv_check_cred(cred, PRIV_VFS_LOOKUP, 0))
3991 priv_granted |= VEXEC;
3992 } else {
3993 /*
3994 * Ensure that at least one execute bit is on. Otherwise,
3995 * a privileged user will always succeed, and we don't want
3996 * this to happen unless the file really is executable.
3997 */
3998 if ((accmode & VEXEC) && ((dac_granted & VEXEC) == 0) &&
3999 (file_mode & (S_IXUSR | S_IXGRP | S_IXOTH)) != 0 &&
4000 !priv_check_cred(cred, PRIV_VFS_EXEC, 0))
4001 priv_granted |= VEXEC;
4002 }
4003
4004 if ((accmode & VREAD) && ((dac_granted & VREAD) == 0) &&
4005 !priv_check_cred(cred, PRIV_VFS_READ, 0))
4006 priv_granted |= VREAD;
4007
4008 if ((accmode & VWRITE) && ((dac_granted & VWRITE) == 0) &&
4009 !priv_check_cred(cred, PRIV_VFS_WRITE, 0))
4010 priv_granted |= (VWRITE | VAPPEND);
4011
4012 if ((accmode & VADMIN) && ((dac_granted & VADMIN) == 0) &&
4013 !priv_check_cred(cred, PRIV_VFS_ADMIN, 0))
4014 priv_granted |= VADMIN;
4015
4016 if ((accmode & (priv_granted | dac_granted)) == accmode) {
4017 /* XXX audit: privilege used */
4018 if (privused != NULL)
4019 *privused = 1;
4020 return (0);
4021 }
4022
4023 return ((accmode & VADMIN) ? EPERM : EACCES);
4024 }
4025
4026 /*
4027 * Credential check based on process requesting service, and per-attribute
4028 * permissions.
4029 */
4030 int
4031 extattr_check_cred(struct vnode *vp, int attrnamespace, struct ucred *cred,
4032 struct thread *td, accmode_t accmode)
4033 {
4034
4035 /*
4036 * Kernel-invoked always succeeds.
4037 */
4038 if (cred == NOCRED)
4039 return (0);
4040
4041 /*
4042 * Do not allow privileged processes in jail to directly manipulate
4043 * system attributes.
4044 */
4045 switch (attrnamespace) {
4046 case EXTATTR_NAMESPACE_SYSTEM:
4047 /* Potentially should be: return (EPERM); */
4048 return (priv_check_cred(cred, PRIV_VFS_EXTATTR_SYSTEM, 0));
4049 case EXTATTR_NAMESPACE_USER:
4050 return (VOP_ACCESS(vp, accmode, cred, td));
4051 default:
4052 return (EPERM);
4053 }
4054 }
4055
4056 #ifdef DEBUG_VFS_LOCKS
4057 /*
4058 * This only exists to supress warnings from unlocked specfs accesses. It is
4059 * no longer ok to have an unlocked VFS.
4060 */
4061 #define IGNORE_LOCK(vp) (panicstr != NULL || (vp) == NULL || \
4062 (vp)->v_type == VCHR || (vp)->v_type == VBAD)
4063
4064 int vfs_badlock_ddb = 1; /* Drop into debugger on violation. */
4065 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_ddb, CTLFLAG_RW, &vfs_badlock_ddb, 0,
4066 "Drop into debugger on lock violation");
4067
4068 int vfs_badlock_mutex = 1; /* Check for interlock across VOPs. */
4069 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_mutex, CTLFLAG_RW, &vfs_badlock_mutex,
4070 0, "Check for interlock across VOPs");
4071
4072 int vfs_badlock_print = 1; /* Print lock violations. */
4073 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_print, CTLFLAG_RW, &vfs_badlock_print,
4074 0, "Print lock violations");
4075
4076 #ifdef KDB
4077 int vfs_badlock_backtrace = 1; /* Print backtrace at lock violations. */
4078 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_backtrace, CTLFLAG_RW,
4079 &vfs_badlock_backtrace, 0, "Print backtrace at lock violations");
4080 #endif
4081
4082 static void
4083 vfs_badlock(const char *msg, const char *str, struct vnode *vp)
4084 {
4085
4086 #ifdef KDB
4087 if (vfs_badlock_backtrace)
4088 kdb_backtrace();
4089 #endif
4090 if (vfs_badlock_print)
4091 printf("%s: %p %s\n", str, (void *)vp, msg);
4092 if (vfs_badlock_ddb)
4093 kdb_enter(KDB_WHY_VFSLOCK, "lock violation");
4094 }
4095
4096 void
4097 assert_vi_locked(struct vnode *vp, const char *str)
4098 {
4099
4100 if (vfs_badlock_mutex && !mtx_owned(VI_MTX(vp)))
4101 vfs_badlock("interlock is not locked but should be", str, vp);
4102 }
4103
4104 void
4105 assert_vi_unlocked(struct vnode *vp, const char *str)
4106 {
4107
4108 if (vfs_badlock_mutex && mtx_owned(VI_MTX(vp)))
4109 vfs_badlock("interlock is locked but should not be", str, vp);
4110 }
4111
4112 void
4113 assert_vop_locked(struct vnode *vp, const char *str)
4114 {
4115 int locked;
4116
4117 if (!IGNORE_LOCK(vp)) {
4118 locked = VOP_ISLOCKED(vp);
4119 if (locked == 0 || locked == LK_EXCLOTHER)
4120 vfs_badlock("is not locked but should be", str, vp);
4121 }
4122 }
4123
4124 void
4125 assert_vop_unlocked(struct vnode *vp, const char *str)
4126 {
4127
4128 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) == LK_EXCLUSIVE)
4129 vfs_badlock("is locked but should not be", str, vp);
4130 }
4131
4132 void
4133 assert_vop_elocked(struct vnode *vp, const char *str)
4134 {
4135
4136 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) != LK_EXCLUSIVE)
4137 vfs_badlock("is not exclusive locked but should be", str, vp);
4138 }
4139
4140 #if 0
4141 void
4142 assert_vop_elocked_other(struct vnode *vp, const char *str)
4143 {
4144
4145 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) != LK_EXCLOTHER)
4146 vfs_badlock("is not exclusive locked by another thread",
4147 str, vp);
4148 }
4149
4150 void
4151 assert_vop_slocked(struct vnode *vp, const char *str)
4152 {
4153
4154 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) != LK_SHARED)
4155 vfs_badlock("is not locked shared but should be", str, vp);
4156 }
4157 #endif /* 0 */
4158 #endif /* DEBUG_VFS_LOCKS */
4159
4160 void
4161 vop_rename_fail(struct vop_rename_args *ap)
4162 {
4163
4164 if (ap->a_tvp != NULL)
4165 vput(ap->a_tvp);
4166 if (ap->a_tdvp == ap->a_tvp)
4167 vrele(ap->a_tdvp);
4168 else
4169 vput(ap->a_tdvp);
4170 vrele(ap->a_fdvp);
4171 vrele(ap->a_fvp);
4172 }
4173
4174 void
4175 vop_rename_pre(void *ap)
4176 {
4177 struct vop_rename_args *a = ap;
4178
4179 #ifdef DEBUG_VFS_LOCKS
4180 if (a->a_tvp)
4181 ASSERT_VI_UNLOCKED(a->a_tvp, "VOP_RENAME");
4182 ASSERT_VI_UNLOCKED(a->a_tdvp, "VOP_RENAME");
4183 ASSERT_VI_UNLOCKED(a->a_fvp, "VOP_RENAME");
4184 ASSERT_VI_UNLOCKED(a->a_fdvp, "VOP_RENAME");
4185
4186 /* Check the source (from). */
4187 if (a->a_tdvp->v_vnlock != a->a_fdvp->v_vnlock &&
4188 (a->a_tvp == NULL || a->a_tvp->v_vnlock != a->a_fdvp->v_vnlock))
4189 ASSERT_VOP_UNLOCKED(a->a_fdvp, "vop_rename: fdvp locked");
4190 if (a->a_tvp == NULL || a->a_tvp->v_vnlock != a->a_fvp->v_vnlock)
4191 ASSERT_VOP_UNLOCKED(a->a_fvp, "vop_rename: fvp locked");
4192
4193 /* Check the target. */
4194 if (a->a_tvp)
4195 ASSERT_VOP_LOCKED(a->a_tvp, "vop_rename: tvp not locked");
4196 ASSERT_VOP_LOCKED(a->a_tdvp, "vop_rename: tdvp not locked");
4197 #endif
4198 if (a->a_tdvp != a->a_fdvp)
4199 vhold(a->a_fdvp);
4200 if (a->a_tvp != a->a_fvp)
4201 vhold(a->a_fvp);
4202 vhold(a->a_tdvp);
4203 if (a->a_tvp)
4204 vhold(a->a_tvp);
4205 }
4206
4207 void
4208 vop_strategy_pre(void *ap)
4209 {
4210 #ifdef DEBUG_VFS_LOCKS
4211 struct vop_strategy_args *a;
4212 struct buf *bp;
4213
4214 a = ap;
4215 bp = a->a_bp;
4216
4217 /*
4218 * Cluster ops lock their component buffers but not the IO container.
4219 */
4220 if ((bp->b_flags & B_CLUSTER) != 0)
4221 return;
4222
4223 if (panicstr == NULL && !BUF_ISLOCKED(bp)) {
4224 if (vfs_badlock_print)
4225 printf(
4226 "VOP_STRATEGY: bp is not locked but should be\n");
4227 if (vfs_badlock_ddb)
4228 kdb_enter(KDB_WHY_VFSLOCK, "lock violation");
4229 }
4230 #endif
4231 }
4232
4233 void
4234 vop_lock_pre(void *ap)
4235 {
4236 #ifdef DEBUG_VFS_LOCKS
4237 struct vop_lock1_args *a = ap;
4238
4239 if ((a->a_flags & LK_INTERLOCK) == 0)
4240 ASSERT_VI_UNLOCKED(a->a_vp, "VOP_LOCK");
4241 else
4242 ASSERT_VI_LOCKED(a->a_vp, "VOP_LOCK");
4243 #endif
4244 }
4245
4246 void
4247 vop_lock_post(void *ap, int rc)
4248 {
4249 #ifdef DEBUG_VFS_LOCKS
4250 struct vop_lock1_args *a = ap;
4251
4252 ASSERT_VI_UNLOCKED(a->a_vp, "VOP_LOCK");
4253 if (rc == 0 && (a->a_flags & LK_EXCLOTHER) == 0)
4254 ASSERT_VOP_LOCKED(a->a_vp, "VOP_LOCK");
4255 #endif
4256 }
4257
4258 void
4259 vop_unlock_pre(void *ap)
4260 {
4261 #ifdef DEBUG_VFS_LOCKS
4262 struct vop_unlock_args *a = ap;
4263
4264 if (a->a_flags & LK_INTERLOCK)
4265 ASSERT_VI_LOCKED(a->a_vp, "VOP_UNLOCK");
4266 ASSERT_VOP_LOCKED(a->a_vp, "VOP_UNLOCK");
4267 #endif
4268 }
4269
4270 void
4271 vop_unlock_post(void *ap, int rc)
4272 {
4273 #ifdef DEBUG_VFS_LOCKS
4274 struct vop_unlock_args *a = ap;
4275
4276 if (a->a_flags & LK_INTERLOCK)
4277 ASSERT_VI_UNLOCKED(a->a_vp, "VOP_UNLOCK");
4278 #endif
4279 }
4280
4281 void
4282 vop_create_post(void *ap, int rc)
4283 {
4284 struct vop_create_args *a = ap;
4285
4286 if (!rc)
4287 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE);
4288 }
4289
4290 void
4291 vop_deleteextattr_post(void *ap, int rc)
4292 {
4293 struct vop_deleteextattr_args *a = ap;
4294
4295 if (!rc)
4296 VFS_KNOTE_LOCKED(a->a_vp, NOTE_ATTRIB);
4297 }
4298
4299 void
4300 vop_link_post(void *ap, int rc)
4301 {
4302 struct vop_link_args *a = ap;
4303
4304 if (!rc) {
4305 VFS_KNOTE_LOCKED(a->a_vp, NOTE_LINK);
4306 VFS_KNOTE_LOCKED(a->a_tdvp, NOTE_WRITE);
4307 }
4308 }
4309
4310 void
4311 vop_mkdir_post(void *ap, int rc)
4312 {
4313 struct vop_mkdir_args *a = ap;
4314
4315 if (!rc)
4316 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE | NOTE_LINK);
4317 }
4318
4319 void
4320 vop_mknod_post(void *ap, int rc)
4321 {
4322 struct vop_mknod_args *a = ap;
4323
4324 if (!rc)
4325 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE);
4326 }
4327
4328 void
4329 vop_remove_post(void *ap, int rc)
4330 {
4331 struct vop_remove_args *a = ap;
4332
4333 if (!rc) {
4334 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE);
4335 VFS_KNOTE_LOCKED(a->a_vp, NOTE_DELETE);
4336 }
4337 }
4338
4339 void
4340 vop_rename_post(void *ap, int rc)
4341 {
4342 struct vop_rename_args *a = ap;
4343
4344 if (!rc) {
4345 VFS_KNOTE_UNLOCKED(a->a_fdvp, NOTE_WRITE);
4346 VFS_KNOTE_UNLOCKED(a->a_tdvp, NOTE_WRITE);
4347 VFS_KNOTE_UNLOCKED(a->a_fvp, NOTE_RENAME);
4348 if (a->a_tvp)
4349 VFS_KNOTE_UNLOCKED(a->a_tvp, NOTE_DELETE);
4350 }
4351 if (a->a_tdvp != a->a_fdvp)
4352 vdrop(a->a_fdvp);
4353 if (a->a_tvp != a->a_fvp)
4354 vdrop(a->a_fvp);
4355 vdrop(a->a_tdvp);
4356 if (a->a_tvp)
4357 vdrop(a->a_tvp);
4358 }
4359
4360 void
4361 vop_rmdir_post(void *ap, int rc)
4362 {
4363 struct vop_rmdir_args *a = ap;
4364
4365 if (!rc) {
4366 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE | NOTE_LINK);
4367 VFS_KNOTE_LOCKED(a->a_vp, NOTE_DELETE);
4368 }
4369 }
4370
4371 void
4372 vop_setattr_post(void *ap, int rc)
4373 {
4374 struct vop_setattr_args *a = ap;
4375
4376 if (!rc)
4377 VFS_KNOTE_LOCKED(a->a_vp, NOTE_ATTRIB);
4378 }
4379
4380 void
4381 vop_setextattr_post(void *ap, int rc)
4382 {
4383 struct vop_setextattr_args *a = ap;
4384
4385 if (!rc)
4386 VFS_KNOTE_LOCKED(a->a_vp, NOTE_ATTRIB);
4387 }
4388
4389 void
4390 vop_symlink_post(void *ap, int rc)
4391 {
4392 struct vop_symlink_args *a = ap;
4393
4394 if (!rc)
4395 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE);
4396 }
4397
4398 static struct knlist fs_knlist;
4399
4400 static void
4401 vfs_event_init(void *arg)
4402 {
4403 knlist_init_mtx(&fs_knlist, NULL);
4404 }
4405 /* XXX - correct order? */
4406 SYSINIT(vfs_knlist, SI_SUB_VFS, SI_ORDER_ANY, vfs_event_init, NULL);
4407
4408 void
4409 vfs_event_signal(fsid_t *fsid, uint32_t event, intptr_t data __unused)
4410 {
4411
4412 KNOTE_UNLOCKED(&fs_knlist, event);
4413 }
4414
4415 static int filt_fsattach(struct knote *kn);
4416 static void filt_fsdetach(struct knote *kn);
4417 static int filt_fsevent(struct knote *kn, long hint);
4418
4419 struct filterops fs_filtops = {
4420 .f_isfd = 0,
4421 .f_attach = filt_fsattach,
4422 .f_detach = filt_fsdetach,
4423 .f_event = filt_fsevent
4424 };
4425
4426 static int
4427 filt_fsattach(struct knote *kn)
4428 {
4429
4430 kn->kn_flags |= EV_CLEAR;
4431 knlist_add(&fs_knlist, kn, 0);
4432 return (0);
4433 }
4434
4435 static void
4436 filt_fsdetach(struct knote *kn)
4437 {
4438
4439 knlist_remove(&fs_knlist, kn, 0);
4440 }
4441
4442 static int
4443 filt_fsevent(struct knote *kn, long hint)
4444 {
4445
4446 kn->kn_fflags |= hint;
4447 return (kn->kn_fflags != 0);
4448 }
4449
4450 static int
4451 sysctl_vfs_ctl(SYSCTL_HANDLER_ARGS)
4452 {
4453 struct vfsidctl vc;
4454 int error;
4455 struct mount *mp;
4456
4457 error = SYSCTL_IN(req, &vc, sizeof(vc));
4458 if (error)
4459 return (error);
4460 if (vc.vc_vers != VFS_CTL_VERS1)
4461 return (EINVAL);
4462 mp = vfs_getvfs(&vc.vc_fsid);
4463 if (mp == NULL)
4464 return (ENOENT);
4465 /* ensure that a specific sysctl goes to the right filesystem. */
4466 if (strcmp(vc.vc_fstypename, "*") != 0 &&
4467 strcmp(vc.vc_fstypename, mp->mnt_vfc->vfc_name) != 0) {
4468 vfs_rel(mp);
4469 return (EINVAL);
4470 }
4471 VCTLTOREQ(&vc, req);
4472 error = VFS_SYSCTL(mp, vc.vc_op, req);
4473 vfs_rel(mp);
4474 return (error);
4475 }
4476
4477 SYSCTL_PROC(_vfs, OID_AUTO, ctl, CTLTYPE_OPAQUE | CTLFLAG_WR,
4478 NULL, 0, sysctl_vfs_ctl, "",
4479 "Sysctl by fsid");
4480
4481 /*
4482 * Function to initialize a va_filerev field sensibly.
4483 * XXX: Wouldn't a random number make a lot more sense ??
4484 */
4485 u_quad_t
4486 init_va_filerev(void)
4487 {
4488 struct bintime bt;
4489
4490 getbinuptime(&bt);
4491 return (((u_quad_t)bt.sec << 32LL) | (bt.frac >> 32LL));
4492 }
4493
4494 static int filt_vfsread(struct knote *kn, long hint);
4495 static int filt_vfswrite(struct knote *kn, long hint);
4496 static int filt_vfsvnode(struct knote *kn, long hint);
4497 static void filt_vfsdetach(struct knote *kn);
4498 static struct filterops vfsread_filtops = {
4499 .f_isfd = 1,
4500 .f_detach = filt_vfsdetach,
4501 .f_event = filt_vfsread
4502 };
4503 static struct filterops vfswrite_filtops = {
4504 .f_isfd = 1,
4505 .f_detach = filt_vfsdetach,
4506 .f_event = filt_vfswrite
4507 };
4508 static struct filterops vfsvnode_filtops = {
4509 .f_isfd = 1,
4510 .f_detach = filt_vfsdetach,
4511 .f_event = filt_vfsvnode
4512 };
4513
4514 static void
4515 vfs_knllock(void *arg)
4516 {
4517 struct vnode *vp = arg;
4518
4519 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
4520 }
4521
4522 static void
4523 vfs_knlunlock(void *arg)
4524 {
4525 struct vnode *vp = arg;
4526
4527 VOP_UNLOCK(vp, 0);
4528 }
4529
4530 static void
4531 vfs_knl_assert_locked(void *arg)
4532 {
4533 #ifdef DEBUG_VFS_LOCKS
4534 struct vnode *vp = arg;
4535
4536 ASSERT_VOP_LOCKED(vp, "vfs_knl_assert_locked");
4537 #endif
4538 }
4539
4540 static void
4541 vfs_knl_assert_unlocked(void *arg)
4542 {
4543 #ifdef DEBUG_VFS_LOCKS
4544 struct vnode *vp = arg;
4545
4546 ASSERT_VOP_UNLOCKED(vp, "vfs_knl_assert_unlocked");
4547 #endif
4548 }
4549
4550 int
4551 vfs_kqfilter(struct vop_kqfilter_args *ap)
4552 {
4553 struct vnode *vp = ap->a_vp;
4554 struct knote *kn = ap->a_kn;
4555 struct knlist *knl;
4556
4557 switch (kn->kn_filter) {
4558 case EVFILT_READ:
4559 kn->kn_fop = &vfsread_filtops;
4560 break;
4561 case EVFILT_WRITE:
4562 kn->kn_fop = &vfswrite_filtops;
4563 break;
4564 case EVFILT_VNODE:
4565 kn->kn_fop = &vfsvnode_filtops;
4566 break;
4567 default:
4568 return (EINVAL);
4569 }
4570
4571 kn->kn_hook = (caddr_t)vp;
4572
4573 v_addpollinfo(vp);
4574 if (vp->v_pollinfo == NULL)
4575 return (ENOMEM);
4576 knl = &vp->v_pollinfo->vpi_selinfo.si_note;
4577 vhold(vp);
4578 knlist_add(knl, kn, 0);
4579
4580 return (0);
4581 }
4582
4583 /*
4584 * Detach knote from vnode
4585 */
4586 static void
4587 filt_vfsdetach(struct knote *kn)
4588 {
4589 struct vnode *vp = (struct vnode *)kn->kn_hook;
4590
4591 KASSERT(vp->v_pollinfo != NULL, ("Missing v_pollinfo"));
4592 knlist_remove(&vp->v_pollinfo->vpi_selinfo.si_note, kn, 0);
4593 vdrop(vp);
4594 }
4595
4596 /*ARGSUSED*/
4597 static int
4598 filt_vfsread(struct knote *kn, long hint)
4599 {
4600 struct vnode *vp = (struct vnode *)kn->kn_hook;
4601 struct vattr va;
4602 int res;
4603
4604 /*
4605 * filesystem is gone, so set the EOF flag and schedule
4606 * the knote for deletion.
4607 */
4608 if (hint == NOTE_REVOKE) {
4609 VI_LOCK(vp);
4610 kn->kn_flags |= (EV_EOF | EV_ONESHOT);
4611 VI_UNLOCK(vp);
4612 return (1);
4613 }
4614
4615 if (VOP_GETATTR(vp, &va, curthread->td_ucred))
4616 return (0);
4617
4618 VI_LOCK(vp);
4619 kn->kn_data = va.va_size - kn->kn_fp->f_offset;
4620 res = (kn->kn_data != 0);
4621 VI_UNLOCK(vp);
4622 return (res);
4623 }
4624
4625 /*ARGSUSED*/
4626 static int
4627 filt_vfswrite(struct knote *kn, long hint)
4628 {
4629 struct vnode *vp = (struct vnode *)kn->kn_hook;
4630
4631 VI_LOCK(vp);
4632
4633 /*
4634 * filesystem is gone, so set the EOF flag and schedule
4635 * the knote for deletion.
4636 */
4637 if (hint == NOTE_REVOKE)
4638 kn->kn_flags |= (EV_EOF | EV_ONESHOT);
4639
4640 kn->kn_data = 0;
4641 VI_UNLOCK(vp);
4642 return (1);
4643 }
4644
4645 static int
4646 filt_vfsvnode(struct knote *kn, long hint)
4647 {
4648 struct vnode *vp = (struct vnode *)kn->kn_hook;
4649 int res;
4650
4651 VI_LOCK(vp);
4652 if (kn->kn_sfflags & hint)
4653 kn->kn_fflags |= hint;
4654 if (hint == NOTE_REVOKE) {
4655 kn->kn_flags |= EV_EOF;
4656 VI_UNLOCK(vp);
4657 return (1);
4658 }
4659 res = (kn->kn_fflags != 0);
4660 VI_UNLOCK(vp);
4661 return (res);
4662 }
4663
4664 int
4665 vfs_read_dirent(struct vop_readdir_args *ap, struct dirent *dp, off_t off)
4666 {
4667 int error;
4668
4669 if (dp->d_reclen > ap->a_uio->uio_resid)
4670 return (ENAMETOOLONG);
4671 error = uiomove(dp, dp->d_reclen, ap->a_uio);
4672 if (error) {
4673 if (ap->a_ncookies != NULL) {
4674 if (ap->a_cookies != NULL)
4675 free(ap->a_cookies, M_TEMP);
4676 ap->a_cookies = NULL;
4677 *ap->a_ncookies = 0;
4678 }
4679 return (error);
4680 }
4681 if (ap->a_ncookies == NULL)
4682 return (0);
4683
4684 KASSERT(ap->a_cookies,
4685 ("NULL ap->a_cookies value with non-NULL ap->a_ncookies!"));
4686
4687 *ap->a_cookies = realloc(*ap->a_cookies,
4688 (*ap->a_ncookies + 1) * sizeof(u_long), M_TEMP, M_WAITOK | M_ZERO);
4689 (*ap->a_cookies)[*ap->a_ncookies] = off;
4690 *ap->a_ncookies += 1;
4691 return (0);
4692 }
4693
4694 /*
4695 * Mark for update the access time of the file if the filesystem
4696 * supports VOP_MARKATIME. This functionality is used by execve and
4697 * mmap, so we want to avoid the I/O implied by directly setting
4698 * va_atime for the sake of efficiency.
4699 */
4700 void
4701 vfs_mark_atime(struct vnode *vp, struct ucred *cred)
4702 {
4703 struct mount *mp;
4704
4705 mp = vp->v_mount;
4706 VFS_ASSERT_GIANT(mp);
4707 ASSERT_VOP_LOCKED(vp, "vfs_mark_atime");
4708 if (mp != NULL && (mp->mnt_flag & (MNT_NOATIME | MNT_RDONLY)) == 0)
4709 (void)VOP_MARKATIME(vp);
4710 }
4711
4712 /*
4713 * The purpose of this routine is to remove granularity from accmode_t,
4714 * reducing it into standard unix access bits - VEXEC, VREAD, VWRITE,
4715 * VADMIN and VAPPEND.
4716 *
4717 * If it returns 0, the caller is supposed to continue with the usual
4718 * access checks using 'accmode' as modified by this routine. If it
4719 * returns nonzero value, the caller is supposed to return that value
4720 * as errno.
4721 *
4722 * Note that after this routine runs, accmode may be zero.
4723 */
4724 int
4725 vfs_unixify_accmode(accmode_t *accmode)
4726 {
4727 /*
4728 * There is no way to specify explicit "deny" rule using
4729 * file mode or POSIX.1e ACLs.
4730 */
4731 if (*accmode & VEXPLICIT_DENY) {
4732 *accmode = 0;
4733 return (0);
4734 }
4735
4736 /*
4737 * None of these can be translated into usual access bits.
4738 * Also, the common case for NFSv4 ACLs is to not contain
4739 * either of these bits. Caller should check for VWRITE
4740 * on the containing directory instead.
4741 */
4742 if (*accmode & (VDELETE_CHILD | VDELETE))
4743 return (EPERM);
4744
4745 if (*accmode & VADMIN_PERMS) {
4746 *accmode &= ~VADMIN_PERMS;
4747 *accmode |= VADMIN;
4748 }
4749
4750 /*
4751 * There is no way to deny VREAD_ATTRIBUTES, VREAD_ACL
4752 * or VSYNCHRONIZE using file mode or POSIX.1e ACL.
4753 */
4754 *accmode &= ~(VSTAT_PERMS | VSYNCHRONIZE);
4755
4756 return (0);
4757 }
4758
4759 /*
4760 * These are helper functions for filesystems to traverse all
4761 * their vnodes. See MNT_VNODE_FOREACH_ALL() in sys/mount.h.
4762 *
4763 * This interface replaces MNT_VNODE_FOREACH.
4764 */
4765
4766 MALLOC_DEFINE(M_VNODE_MARKER, "vnodemarker", "vnode marker");
4767
4768 struct vnode *
4769 __mnt_vnode_next_all(struct vnode **mvp, struct mount *mp)
4770 {
4771 struct vnode *vp;
4772
4773 if (should_yield())
4774 kern_yield(PRI_UNCHANGED);
4775 MNT_ILOCK(mp);
4776 KASSERT((*mvp)->v_mount == mp, ("marker vnode mount list mismatch"));
4777 vp = TAILQ_NEXT(*mvp, v_nmntvnodes);
4778 while (vp != NULL && (vp->v_type == VMARKER ||
4779 (vp->v_iflag & VI_DOOMED) != 0))
4780 vp = TAILQ_NEXT(vp, v_nmntvnodes);
4781
4782 /* Check if we are done */
4783 if (vp == NULL) {
4784 __mnt_vnode_markerfree_all(mvp, mp);
4785 /* MNT_IUNLOCK(mp); -- done in above function */
4786 mtx_assert(MNT_MTX(mp), MA_NOTOWNED);
4787 return (NULL);
4788 }
4789 TAILQ_REMOVE(&mp->mnt_nvnodelist, *mvp, v_nmntvnodes);
4790 TAILQ_INSERT_AFTER(&mp->mnt_nvnodelist, vp, *mvp, v_nmntvnodes);
4791 VI_LOCK(vp);
4792 MNT_IUNLOCK(mp);
4793 return (vp);
4794 }
4795
4796 struct vnode *
4797 __mnt_vnode_first_all(struct vnode **mvp, struct mount *mp)
4798 {
4799 struct vnode *vp;
4800
4801 *mvp = malloc(sizeof(struct vnode), M_VNODE_MARKER, M_WAITOK | M_ZERO);
4802 MNT_ILOCK(mp);
4803 MNT_REF(mp);
4804 (*mvp)->v_type = VMARKER;
4805
4806 vp = TAILQ_FIRST(&mp->mnt_nvnodelist);
4807 while (vp != NULL && (vp->v_type == VMARKER ||
4808 (vp->v_iflag & VI_DOOMED) != 0))
4809 vp = TAILQ_NEXT(vp, v_nmntvnodes);
4810
4811 /* Check if we are done */
4812 if (vp == NULL) {
4813 MNT_REL(mp);
4814 MNT_IUNLOCK(mp);
4815 free(*mvp, M_VNODE_MARKER);
4816 *mvp = NULL;
4817 return (NULL);
4818 }
4819 (*mvp)->v_mount = mp;
4820 TAILQ_INSERT_AFTER(&mp->mnt_nvnodelist, vp, *mvp, v_nmntvnodes);
4821 VI_LOCK(vp);
4822 MNT_IUNLOCK(mp);
4823 return (vp);
4824 }
4825
4826
4827 void
4828 __mnt_vnode_markerfree_all(struct vnode **mvp, struct mount *mp)
4829 {
4830
4831 if (*mvp == NULL) {
4832 MNT_IUNLOCK(mp);
4833 return;
4834 }
4835
4836 mtx_assert(MNT_MTX(mp), MA_OWNED);
4837
4838 KASSERT((*mvp)->v_mount == mp, ("marker vnode mount list mismatch"));
4839 TAILQ_REMOVE(&mp->mnt_nvnodelist, *mvp, v_nmntvnodes);
4840 MNT_REL(mp);
4841 MNT_IUNLOCK(mp);
4842 free(*mvp, M_VNODE_MARKER);
4843 *mvp = NULL;
4844 }
4845
4846 /*
4847 * These are helper functions for filesystems to traverse their
4848 * active vnodes. See MNT_VNODE_FOREACH_ACTIVE() in sys/mount.h
4849 */
4850 static void
4851 mnt_vnode_markerfree_active(struct vnode **mvp, struct mount *mp)
4852 {
4853
4854 KASSERT((*mvp)->v_mount == mp, ("marker vnode mount list mismatch"));
4855
4856 MNT_ILOCK(mp);
4857 MNT_REL(mp);
4858 MNT_IUNLOCK(mp);
4859 free(*mvp, M_VNODE_MARKER);
4860 *mvp = NULL;
4861 }
4862
4863 #ifdef SMP
4864 #define ALWAYS_YIELD (mp_ncpus == 1)
4865 #else
4866 #define ALWAYS_YIELD 1
4867 #endif
4868
4869 static struct vnode *
4870 mnt_vnode_next_active(struct vnode **mvp, struct mount *mp)
4871 {
4872 struct vnode *vp, *nvp;
4873
4874 mtx_assert(&vnode_free_list_mtx, MA_OWNED);
4875 KASSERT((*mvp)->v_mount == mp, ("marker vnode mount list mismatch"));
4876 restart:
4877 vp = TAILQ_NEXT(*mvp, v_actfreelist);
4878 TAILQ_REMOVE(&mp->mnt_activevnodelist, *mvp, v_actfreelist);
4879 while (vp != NULL) {
4880 if (vp->v_type == VMARKER) {
4881 vp = TAILQ_NEXT(vp, v_actfreelist);
4882 continue;
4883 }
4884 if (!VI_TRYLOCK(vp)) {
4885 if (ALWAYS_YIELD || should_yield()) {
4886 TAILQ_INSERT_BEFORE(vp, *mvp, v_actfreelist);
4887 mtx_unlock(&vnode_free_list_mtx);
4888 pause("vnacti", 1);
4889 mtx_lock(&vnode_free_list_mtx);
4890 goto restart;
4891 }
4892 continue;
4893 }
4894 KASSERT(vp->v_type != VMARKER, ("locked marker %p", vp));
4895 KASSERT(vp->v_mount == mp || vp->v_mount == NULL,
4896 ("alien vnode on the active list %p %p", vp, mp));
4897 if (vp->v_mount == mp && (vp->v_iflag & VI_DOOMED) == 0)
4898 break;
4899 nvp = TAILQ_NEXT(vp, v_actfreelist);
4900 VI_UNLOCK(vp);
4901 vp = nvp;
4902 }
4903
4904 /* Check if we are done */
4905 if (vp == NULL) {
4906 mtx_unlock(&vnode_free_list_mtx);
4907 mnt_vnode_markerfree_active(mvp, mp);
4908 return (NULL);
4909 }
4910 TAILQ_INSERT_AFTER(&mp->mnt_activevnodelist, vp, *mvp, v_actfreelist);
4911 mtx_unlock(&vnode_free_list_mtx);
4912 ASSERT_VI_LOCKED(vp, "active iter");
4913 KASSERT((vp->v_iflag & VI_ACTIVE) != 0, ("Non-active vp %p", vp));
4914 return (vp);
4915 }
4916 #undef ALWAYS_YIELD
4917
4918 struct vnode *
4919 __mnt_vnode_next_active(struct vnode **mvp, struct mount *mp)
4920 {
4921
4922 if (should_yield())
4923 kern_yield(PRI_UNCHANGED);
4924 mtx_lock(&vnode_free_list_mtx);
4925 return (mnt_vnode_next_active(mvp, mp));
4926 }
4927
4928 struct vnode *
4929 __mnt_vnode_first_active(struct vnode **mvp, struct mount *mp)
4930 {
4931 struct vnode *vp;
4932
4933 *mvp = malloc(sizeof(struct vnode), M_VNODE_MARKER, M_WAITOK | M_ZERO);
4934 MNT_ILOCK(mp);
4935 MNT_REF(mp);
4936 MNT_IUNLOCK(mp);
4937 (*mvp)->v_type = VMARKER;
4938 (*mvp)->v_mount = mp;
4939
4940 mtx_lock(&vnode_free_list_mtx);
4941 vp = TAILQ_FIRST(&mp->mnt_activevnodelist);
4942 if (vp == NULL) {
4943 mtx_unlock(&vnode_free_list_mtx);
4944 mnt_vnode_markerfree_active(mvp, mp);
4945 return (NULL);
4946 }
4947 TAILQ_INSERT_BEFORE(vp, *mvp, v_actfreelist);
4948 return (mnt_vnode_next_active(mvp, mp));
4949 }
4950
4951 void
4952 __mnt_vnode_markerfree_active(struct vnode **mvp, struct mount *mp)
4953 {
4954
4955 if (*mvp == NULL)
4956 return;
4957
4958 mtx_lock(&vnode_free_list_mtx);
4959 TAILQ_REMOVE(&mp->mnt_activevnodelist, *mvp, v_actfreelist);
4960 mtx_unlock(&vnode_free_list_mtx);
4961 mnt_vnode_markerfree_active(mvp, mp);
4962 }
Cache object: 33f97d4708ee6b85070c3ccfef07d7fb
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