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.
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
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.
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
34 * @(#)vfs_subr.c 8.31 (Berkeley) 5/26/95
38 * External virtual filesystem routines
41 #include <sys/cdefs.h>
42 __FBSDID("$FreeBSD$");
47 #include <sys/param.h>
48 #include <sys/systm.h>
52 #include <sys/dirent.h>
53 #include <sys/event.h>
54 #include <sys/eventhandler.h>
55 #include <sys/extattr.h>
57 #include <sys/fcntl.h>
59 #include <sys/kernel.h>
60 #include <sys/kthread.h>
62 #include <sys/malloc.h>
63 #include <sys/mount.h>
64 #include <sys/namei.h>
65 #include <sys/reboot.h>
66 #include <sys/sleepqueue.h>
68 #include <sys/sysctl.h>
69 #include <sys/syslog.h>
70 #include <sys/vmmeter.h>
71 #include <sys/vnode.h>
73 #include <machine/stdarg.h>
76 #include <vm/vm_object.h>
77 #include <vm/vm_extern.h>
79 #include <vm/vm_map.h>
80 #include <vm/vm_page.h>
81 #include <vm/vm_kern.h>
84 static MALLOC_DEFINE(M_NETADDR, "subr_export_host", "Export host address structure");
86 static void delmntque(struct vnode *vp);
87 static void insmntque(struct vnode *vp, struct mount *mp);
88 static int flushbuflist(struct bufv *bufv, int flags, struct bufobj *bo,
89 int slpflag, int slptimeo);
90 static void syncer_shutdown(void *arg, int howto);
91 static int vtryrecycle(struct vnode *vp);
92 static void vbusy(struct vnode *vp);
93 static void vdropl(struct vnode *vp);
94 static void vinactive(struct vnode *, struct thread *);
95 static void v_incr_usecount(struct vnode *);
96 static void v_decr_usecount(struct vnode *);
97 static void v_decr_useonly(struct vnode *);
98 static void v_upgrade_usecount(struct vnode *);
99 static void vfree(struct vnode *);
100 static void vnlru_free(int);
101 static void vdestroy(struct vnode *);
102 static void vgonel(struct vnode *);
103 static void vfs_knllock(void *arg);
104 static void vfs_knlunlock(void *arg);
105 static int vfs_knllocked(void *arg);
109 * Enable Giant pushdown based on whether or not the vm is mpsafe in this
110 * build. Without mpsafevm the buffer cache can not run Giant free.
112 #if defined(__alpha__) || defined(__amd64__) || defined(__i386__) || \
113 defined(__ia64__) || defined(__sparc64__)
118 TUNABLE_INT("debug.mpsafevfs", &mpsafe_vfs);
119 SYSCTL_INT(_debug, OID_AUTO, mpsafevfs, CTLFLAG_RD, &mpsafe_vfs, 0,
123 * Number of vnodes in existence. Increased whenever getnewvnode()
124 * allocates a new vnode, never decreased.
126 static unsigned long numvnodes;
128 SYSCTL_LONG(_vfs, OID_AUTO, numvnodes, CTLFLAG_RD, &numvnodes, 0, "");
131 * Conversion tables for conversion from vnode types to inode formats
134 enum vtype iftovt_tab[16] = {
135 VNON, VFIFO, VCHR, VNON, VDIR, VNON, VBLK, VNON,
136 VREG, VNON, VLNK, VNON, VSOCK, VNON, VNON, VBAD,
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
144 * List of vnodes that are ready for recycling.
146 static TAILQ_HEAD(freelst, vnode) vnode_free_list;
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.
153 static u_long wantfreevnodes;
154 SYSCTL_LONG(_vfs, OID_AUTO, wantfreevnodes, CTLFLAG_RW, &wantfreevnodes, 0, "");
155 /* Number of vnodes in the free list. */
156 static u_long freevnodes;
157 SYSCTL_LONG(_vfs, OID_AUTO, freevnodes, CTLFLAG_RD, &freevnodes, 0, "");
160 * Various variables used for debugging the new implementation of
162 * XXX these are probably of (very) limited utility now.
164 static int reassignbufcalls;
165 SYSCTL_INT(_vfs, OID_AUTO, reassignbufcalls, CTLFLAG_RW, &reassignbufcalls, 0, "");
168 * Cache for the mount type id assigned to NFS. This is used for
169 * special checks in nfs/nfs_nqlease.c and vm/vnode_pager.c.
171 int nfs_mount_type = -1;
173 /* To keep more than one thread at a time from running vfs_getnewfsid */
174 static struct mtx mntid_mtx;
177 * Lock for any access to the following:
182 static struct mtx vnode_free_list_mtx;
184 /* Publicly exported FS */
185 struct nfs_public nfs_pub;
187 /* Zone for allocation of new vnodes - used exclusively by getnewvnode() */
188 static uma_zone_t vnode_zone;
189 static uma_zone_t vnodepoll_zone;
191 /* Set to 1 to print out reclaim of active vnodes */
195 * The workitem queue.
197 * It is useful to delay writes of file data and filesystem metadata
198 * for tens of seconds so that quickly created and deleted files need
199 * not waste disk bandwidth being created and removed. To realize this,
200 * we append vnodes to a "workitem" queue. When running with a soft
201 * updates implementation, most pending metadata dependencies should
202 * not wait for more than a few seconds. Thus, mounted on block devices
203 * are delayed only about a half the time that file data is delayed.
204 * Similarly, directory updates are more critical, so are only delayed
205 * about a third the time that file data is delayed. Thus, there are
206 * SYNCER_MAXDELAY queues that are processed round-robin at a rate of
207 * one each second (driven off the filesystem syncer process). The
208 * syncer_delayno variable indicates the next queue that is to be processed.
209 * Items that need to be processed soon are placed in this queue:
211 * syncer_workitem_pending[syncer_delayno]
213 * A delay of fifteen seconds is done by placing the request fifteen
214 * entries later in the queue:
216 * syncer_workitem_pending[(syncer_delayno + 15) & syncer_mask]
219 static int syncer_delayno;
220 static long syncer_mask;
221 LIST_HEAD(synclist, bufobj);
222 static struct synclist *syncer_workitem_pending;
224 * The sync_mtx protects:
229 * syncer_workitem_pending
230 * syncer_worklist_len
233 static struct mtx sync_mtx;
235 #define SYNCER_MAXDELAY 32
236 static int syncer_maxdelay = SYNCER_MAXDELAY; /* maximum delay time */
237 static int syncdelay = 30; /* max time to delay syncing data */
238 static int filedelay = 30; /* time to delay syncing files */
239 SYSCTL_INT(_kern, OID_AUTO, filedelay, CTLFLAG_RW, &filedelay, 0, "");
240 static int dirdelay = 29; /* time to delay syncing directories */
241 SYSCTL_INT(_kern, OID_AUTO, dirdelay, CTLFLAG_RW, &dirdelay, 0, "");
242 static int metadelay = 28; /* time to delay syncing metadata */
243 SYSCTL_INT(_kern, OID_AUTO, metadelay, CTLFLAG_RW, &metadelay, 0, "");
244 static int rushjob; /* number of slots to run ASAP */
245 static int stat_rush_requests; /* number of times I/O speeded up */
246 SYSCTL_INT(_debug, OID_AUTO, rush_requests, CTLFLAG_RW, &stat_rush_requests, 0, "");
249 * When shutting down the syncer, run it at four times normal speed.
251 #define SYNCER_SHUTDOWN_SPEEDUP 4
252 static int sync_vnode_count;
253 static int syncer_worklist_len;
254 static enum { SYNCER_RUNNING, SYNCER_SHUTTING_DOWN, SYNCER_FINAL_DELAY }
258 * Number of vnodes we want to exist at any one time. This is mostly used
259 * to size hash tables in vnode-related code. It is normally not used in
260 * getnewvnode(), as wantfreevnodes is normally nonzero.)
262 * XXX desiredvnodes is historical cruft and should not exist.
265 SYSCTL_INT(_kern, KERN_MAXVNODES, maxvnodes, CTLFLAG_RW,
266 &desiredvnodes, 0, "Maximum number of vnodes");
267 SYSCTL_INT(_kern, OID_AUTO, minvnodes, CTLFLAG_RW,
268 &wantfreevnodes, 0, "Minimum number of vnodes (legacy)");
269 static int vnlru_nowhere;
270 SYSCTL_INT(_debug, OID_AUTO, vnlru_nowhere, CTLFLAG_RW,
271 &vnlru_nowhere, 0, "Number of times the vnlru process ran without success");
274 * Macros to control when a vnode is freed and recycled. All require
275 * the vnode interlock.
277 #define VCANRECYCLE(vp) (((vp)->v_iflag & VI_FREE) && !(vp)->v_holdcnt)
278 #define VSHOULDFREE(vp) (!((vp)->v_iflag & VI_FREE) && !(vp)->v_holdcnt)
279 #define VSHOULDBUSY(vp) (((vp)->v_iflag & VI_FREE) && (vp)->v_holdcnt)
283 * Initialize the vnode management data structures.
285 #ifndef MAXVNODES_MAX
286 #define MAXVNODES_MAX 100000
289 vntblinit(void *dummy __unused)
293 * Desiredvnodes is a function of the physical memory size and
294 * the kernel's heap size. Specifically, desiredvnodes scales
295 * in proportion to the physical memory size until two fifths
296 * of the kernel's heap size is consumed by vnodes and vm
299 desiredvnodes = min(maxproc + cnt.v_page_count / 4, 2 * vm_kmem_size /
300 (5 * (sizeof(struct vm_object) + sizeof(struct vnode))));
301 if (desiredvnodes > MAXVNODES_MAX) {
303 printf("Reducing kern.maxvnodes %d -> %d\n",
304 desiredvnodes, MAXVNODES_MAX);
305 desiredvnodes = MAXVNODES_MAX;
307 wantfreevnodes = desiredvnodes / 4;
308 mtx_init(&mntid_mtx, "mntid", NULL, MTX_DEF);
309 TAILQ_INIT(&vnode_free_list);
310 mtx_init(&vnode_free_list_mtx, "vnode_free_list", NULL, MTX_DEF);
311 vnode_zone = uma_zcreate("VNODE", sizeof (struct vnode), NULL, NULL,
312 NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_NOFREE);
313 vnodepoll_zone = uma_zcreate("VNODEPOLL", sizeof (struct vpollinfo),
314 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_NOFREE);
316 * Initialize the filesystem syncer.
318 syncer_workitem_pending = hashinit(syncer_maxdelay, M_VNODE,
320 syncer_maxdelay = syncer_mask + 1;
321 mtx_init(&sync_mtx, "Syncer mtx", NULL, MTX_DEF);
323 SYSINIT(vfs, SI_SUB_VFS, SI_ORDER_FIRST, vntblinit, NULL)
327 * Mark a mount point as busy. Used to synchronize access and to delay
328 * unmounting. Interlock is not released on failure.
331 vfs_busy(struct mount *mp, int flags, struct mtx *interlkp,
338 if (mp->mnt_kern_flag & MNTK_UNMOUNT) {
339 if (flags & LK_NOWAIT) {
345 mtx_unlock(interlkp);
346 mp->mnt_kern_flag |= MNTK_MWAIT;
348 * Since all busy locks are shared except the exclusive
349 * lock granted when unmounting, the only place that a
350 * wakeup needs to be done is at the release of the
351 * exclusive lock at the end of dounmount.
353 msleep(mp, MNT_MTX(mp), PVFS, "vfs_busy", 0);
361 mtx_unlock(interlkp);
362 lkflags = LK_SHARED | LK_INTERLOCK;
363 if (lockmgr(&mp->mnt_lock, lkflags, MNT_MTX(mp), td))
364 panic("vfs_busy: unexpected lock failure");
370 * Free a busy filesystem.
373 vfs_unbusy(struct mount *mp, struct thread *td)
376 lockmgr(&mp->mnt_lock, LK_RELEASE, NULL, td);
380 * Lookup a mount point by filesystem identifier.
383 vfs_getvfs(fsid_t *fsid)
387 mtx_lock(&mountlist_mtx);
388 TAILQ_FOREACH(mp, &mountlist, mnt_list) {
389 if (mp->mnt_stat.f_fsid.val[0] == fsid->val[0] &&
390 mp->mnt_stat.f_fsid.val[1] == fsid->val[1]) {
391 mtx_unlock(&mountlist_mtx);
395 mtx_unlock(&mountlist_mtx);
396 return ((struct mount *) 0);
400 * Check if a user can access priveledged mount options.
403 vfs_suser(struct mount *mp, struct thread *td)
407 if ((mp->mnt_flag & MNT_USER) == 0 ||
408 mp->mnt_cred->cr_uid != td->td_ucred->cr_uid) {
409 if ((error = suser(td)) != 0)
416 * Get a new unique fsid. Try to make its val[0] unique, since this value
417 * will be used to create fake device numbers for stat(). Also try (but
418 * not so hard) make its val[0] unique mod 2^16, since some emulators only
419 * support 16-bit device numbers. We end up with unique val[0]'s for the
420 * first 2^16 calls and unique val[0]'s mod 2^16 for the first 2^8 calls.
422 * Keep in mind that several mounts may be running in parallel. Starting
423 * the search one past where the previous search terminated is both a
424 * micro-optimization and a defense against returning the same fsid to
428 vfs_getnewfsid(struct mount *mp)
430 static u_int16_t mntid_base;
434 mtx_lock(&mntid_mtx);
435 mtype = mp->mnt_vfc->vfc_typenum;
436 tfsid.val[1] = mtype;
437 mtype = (mtype & 0xFF) << 24;
439 tfsid.val[0] = makedev(255,
440 mtype | ((mntid_base & 0xFF00) << 8) | (mntid_base & 0xFF));
442 if (vfs_getvfs(&tfsid) == NULL)
445 mp->mnt_stat.f_fsid.val[0] = tfsid.val[0];
446 mp->mnt_stat.f_fsid.val[1] = tfsid.val[1];
447 mtx_unlock(&mntid_mtx);
451 * Knob to control the precision of file timestamps:
453 * 0 = seconds only; nanoseconds zeroed.
454 * 1 = seconds and nanoseconds, accurate within 1/HZ.
455 * 2 = seconds and nanoseconds, truncated to microseconds.
456 * >=3 = seconds and nanoseconds, maximum precision.
458 enum { TSP_SEC, TSP_HZ, TSP_USEC, TSP_NSEC };
460 static int timestamp_precision = TSP_SEC;
461 SYSCTL_INT(_vfs, OID_AUTO, timestamp_precision, CTLFLAG_RW,
462 ×tamp_precision, 0, "");
465 * Get a current timestamp.
468 vfs_timestamp(struct timespec *tsp)
472 switch (timestamp_precision) {
474 tsp->tv_sec = time_second;
482 TIMEVAL_TO_TIMESPEC(&tv, tsp);
492 * Set vnode attributes to VNOVAL
495 vattr_null(struct vattr *vap)
499 vap->va_size = VNOVAL;
500 vap->va_bytes = VNOVAL;
501 vap->va_mode = VNOVAL;
502 vap->va_nlink = VNOVAL;
503 vap->va_uid = VNOVAL;
504 vap->va_gid = VNOVAL;
505 vap->va_fsid = VNOVAL;
506 vap->va_fileid = VNOVAL;
507 vap->va_blocksize = VNOVAL;
508 vap->va_rdev = VNOVAL;
509 vap->va_atime.tv_sec = VNOVAL;
510 vap->va_atime.tv_nsec = VNOVAL;
511 vap->va_mtime.tv_sec = VNOVAL;
512 vap->va_mtime.tv_nsec = VNOVAL;
513 vap->va_ctime.tv_sec = VNOVAL;
514 vap->va_ctime.tv_nsec = VNOVAL;
515 vap->va_birthtime.tv_sec = VNOVAL;
516 vap->va_birthtime.tv_nsec = VNOVAL;
517 vap->va_flags = VNOVAL;
518 vap->va_gen = VNOVAL;
523 * This routine is called when we have too many vnodes. It attempts
524 * to free <count> vnodes and will potentially free vnodes that still
525 * have VM backing store (VM backing store is typically the cause
526 * of a vnode blowout so we want to do this). Therefore, this operation
527 * is not considered cheap.
529 * A number of conditions may prevent a vnode from being reclaimed.
530 * the buffer cache may have references on the vnode, a directory
531 * vnode may still have references due to the namei cache representing
532 * underlying files, or the vnode may be in active use. It is not
533 * desireable to reuse such vnodes. These conditions may cause the
534 * number of vnodes to reach some minimum value regardless of what
535 * you set kern.maxvnodes to. Do not set kern.maxvnodes too low.
538 vlrureclaim(struct mount *mp)
548 * Calculate the trigger point, don't allow user
549 * screwups to blow us up. This prevents us from
550 * recycling vnodes with lots of resident pages. We
551 * aren't trying to free memory, we are trying to
554 usevnodes = desiredvnodes;
557 trigger = cnt.v_page_count * 2 / usevnodes;
560 vn_start_write(NULL, &mp, V_WAIT);
562 count = mp->mnt_nvnodelistsize / 10 + 1;
564 vp = TAILQ_FIRST(&mp->mnt_nvnodelist);
565 while (vp != NULL && vp->v_type == VMARKER)
566 vp = TAILQ_NEXT(vp, v_nmntvnodes);
569 TAILQ_REMOVE(&mp->mnt_nvnodelist, vp, v_nmntvnodes);
570 TAILQ_INSERT_TAIL(&mp->mnt_nvnodelist, vp, v_nmntvnodes);
575 * If it's been deconstructed already, it's still
576 * referenced, or it exceeds the trigger, skip it.
578 if (vp->v_usecount || !LIST_EMPTY(&(vp)->v_cache_src) ||
579 (vp->v_iflag & VI_DOOMED) != 0 || (vp->v_object != NULL &&
580 vp->v_object->resident_page_count > trigger)) {
586 if (VOP_LOCK(vp, LK_INTERLOCK|LK_EXCLUSIVE|LK_NOWAIT, td)) {
588 goto next_iter_mntunlocked;
592 * v_usecount may have been bumped after VOP_LOCK() dropped
593 * the vnode interlock and before it was locked again.
595 * It is not necessary to recheck VI_DOOMED because it can
596 * only be set by another thread that holds both the vnode
597 * lock and vnode interlock. If another thread has the
598 * vnode lock before we get to VOP_LOCK() and obtains the
599 * vnode interlock after VOP_LOCK() drops the vnode
600 * interlock, the other thread will be unable to drop the
601 * vnode lock before our VOP_LOCK() call fails.
603 if (vp->v_usecount || !LIST_EMPTY(&(vp)->v_cache_src) ||
604 (vp->v_object != NULL &&
605 vp->v_object->resident_page_count > trigger)) {
606 VOP_UNLOCK(vp, LK_INTERLOCK, td);
607 goto next_iter_mntunlocked;
609 KASSERT((vp->v_iflag & VI_DOOMED) == 0,
610 ("VI_DOOMED unexpectedly detected in vlrureclaim()"));
612 VOP_UNLOCK(vp, 0, td);
615 next_iter_mntunlocked:
616 if ((count % 256) != 0)
620 if ((count % 256) != 0)
629 vn_finished_write(mp);
634 * Attempt to keep the free list at wantfreevnodes length.
637 vnlru_free(int count)
641 mtx_assert(&vnode_free_list_mtx, MA_OWNED);
642 for (; count > 0; count--) {
643 vp = TAILQ_FIRST(&vnode_free_list);
645 * The list can be modified while the free_list_mtx
646 * has been dropped and vp could be NULL here.
650 VNASSERT(vp->v_op != NULL, vp,
651 ("vnlru_free: vnode already reclaimed."));
652 TAILQ_REMOVE(&vnode_free_list, vp, v_freelist);
654 * Don't recycle if we can't get the interlock.
656 if (!VI_TRYLOCK(vp)) {
657 TAILQ_INSERT_TAIL(&vnode_free_list, vp, v_freelist);
660 VNASSERT(VCANRECYCLE(vp), vp,
661 ("vp inconsistent on freelist"));
663 vp->v_iflag &= ~VI_FREE;
665 mtx_unlock(&vnode_free_list_mtx);
669 * If the recycled succeeded this vdrop will actually free
670 * the vnode. If not it will simply place it back on
674 mtx_lock(&vnode_free_list_mtx);
678 * Attempt to recycle vnodes in a context that is always safe to block.
679 * Calling vlrurecycle() from the bowels of filesystem code has some
680 * interesting deadlock problems.
682 static struct proc *vnlruproc;
683 static int vnlruproc_sig;
688 struct mount *mp, *nmp;
690 struct proc *p = vnlruproc;
691 struct thread *td = FIRST_THREAD_IN_PROC(p);
695 EVENTHANDLER_REGISTER(shutdown_pre_sync, kproc_shutdown, p,
699 kthread_suspend_check(p);
700 mtx_lock(&vnode_free_list_mtx);
701 if (freevnodes > wantfreevnodes)
702 vnlru_free(freevnodes - wantfreevnodes);
703 if (numvnodes <= desiredvnodes * 9 / 10) {
705 wakeup(&vnlruproc_sig);
706 msleep(vnlruproc, &vnode_free_list_mtx,
707 PVFS|PDROP, "vlruwt", hz);
710 mtx_unlock(&vnode_free_list_mtx);
712 mtx_lock(&mountlist_mtx);
713 for (mp = TAILQ_FIRST(&mountlist); mp != NULL; mp = nmp) {
715 if (vfs_busy(mp, LK_NOWAIT, &mountlist_mtx, td)) {
716 nmp = TAILQ_NEXT(mp, mnt_list);
719 if (!VFS_NEEDSGIANT(mp)) {
724 done += vlrureclaim(mp);
727 mtx_lock(&mountlist_mtx);
728 nmp = TAILQ_NEXT(mp, mnt_list);
731 mtx_unlock(&mountlist_mtx);
734 /* These messages are temporary debugging aids */
735 if (vnlru_nowhere < 5)
736 printf("vnlru process getting nowhere..\n");
737 else if (vnlru_nowhere == 5)
738 printf("vnlru process messages stopped.\n");
741 tsleep(vnlruproc, PPAUSE, "vlrup", hz * 3);
747 static struct kproc_desc vnlru_kp = {
752 SYSINIT(vnlru, SI_SUB_KTHREAD_UPDATE, SI_ORDER_FIRST, kproc_start, &vnlru_kp)
755 * Routines having to do with the management of the vnode table.
759 vdestroy(struct vnode *vp)
763 CTR1(KTR_VFS, "vdestroy vp %p", vp);
764 mtx_lock(&vnode_free_list_mtx);
766 mtx_unlock(&vnode_free_list_mtx);
768 VNASSERT((vp->v_iflag & VI_FREE) == 0, vp,
769 ("cleaned vnode still on the free list."));
770 VNASSERT(vp->v_data == NULL, vp, ("cleaned vnode isn't"));
771 VNASSERT(vp->v_holdcnt == 0, vp, ("Non-zero hold count"));
772 VNASSERT(vp->v_usecount == 0, vp, ("Non-zero use count"));
773 VNASSERT(vp->v_writecount == 0, vp, ("Non-zero write count"));
774 VNASSERT(bo->bo_numoutput == 0, vp, ("Clean vnode has pending I/O's"));
775 VNASSERT(bo->bo_clean.bv_cnt == 0, vp, ("cleanbufcnt not 0"));
776 VNASSERT(bo->bo_clean.bv_root == NULL, vp, ("cleanblkroot not NULL"));
777 VNASSERT(bo->bo_dirty.bv_cnt == 0, vp, ("dirtybufcnt not 0"));
778 VNASSERT(bo->bo_dirty.bv_root == NULL, vp, ("dirtyblkroot not NULL"));
779 VNASSERT(TAILQ_EMPTY(&vp->v_cache_dst), vp, ("vp has namecache dst"));
780 VNASSERT(LIST_EMPTY(&vp->v_cache_src), vp, ("vp has namecache src"));
783 mac_destroy_vnode(vp);
785 if (vp->v_pollinfo != NULL) {
786 knlist_destroy(&vp->v_pollinfo->vpi_selinfo.si_note);
787 mtx_destroy(&vp->v_pollinfo->vpi_lock);
788 uma_zfree(vnodepoll_zone, vp->v_pollinfo);
791 /* XXX Elsewhere we can detect an already freed vnode via NULL v_op. */
794 lockdestroy(vp->v_vnlock);
795 mtx_destroy(&vp->v_interlock);
796 uma_zfree(vnode_zone, vp);
800 * Try to recycle a freed vnode. We abort if anyone picks up a reference
801 * before we actually vgone(). This function must be called with the vnode
802 * held to prevent the vnode from being returned to the free list midway
806 vtryrecycle(struct vnode *vp)
808 struct thread *td = curthread;
811 CTR1(KTR_VFS, "vtryrecycle: trying vp %p", vp);
812 VNASSERT(vp->v_holdcnt, vp,
813 ("vtryrecycle: Recycling vp %p without a reference.", vp));
815 * This vnode may found and locked via some other list, if so we
816 * can't recycle it yet.
818 if (VOP_LOCK(vp, LK_EXCLUSIVE | LK_NOWAIT, td) != 0)
819 return (EWOULDBLOCK);
821 * Don't recycle if its filesystem is being suspended.
823 if (vn_start_write(vp, &vnmp, V_NOWAIT) != 0) {
824 VOP_UNLOCK(vp, 0, td);
828 * If we got this far, we need to acquire the interlock and see if
829 * anyone picked up this vnode from another list. If not, we will
830 * mark it with DOOMED via vgonel() so that anyone who does find it
834 if (vp->v_usecount) {
835 VOP_UNLOCK(vp, LK_INTERLOCK, td);
836 vn_finished_write(vnmp);
839 if ((vp->v_iflag & VI_DOOMED) == 0)
841 VOP_UNLOCK(vp, LK_INTERLOCK, td);
842 vn_finished_write(vnmp);
843 CTR1(KTR_VFS, "vtryrecycle: recycled vp %p", vp);
848 * Return the next vnode from the free list.
851 getnewvnode(const char *tag, struct mount *mp, struct vop_vector *vops,
854 struct vnode *vp = NULL;
857 mtx_lock(&vnode_free_list_mtx);
859 * Lend our context to reclaim vnodes if they've exceeded the max.
861 if (freevnodes > wantfreevnodes)
864 * Wait for available vnodes.
866 if (numvnodes > desiredvnodes) {
867 if (vnlruproc_sig == 0) {
868 vnlruproc_sig = 1; /* avoid unnecessary wakeups */
871 msleep(&vnlruproc_sig, &vnode_free_list_mtx, PVFS,
873 #if 0 /* XXX Not all VFS_VGET/ffs_vget callers check returns. */
874 if (numvnodes > desiredvnodes) {
875 mtx_unlock(&vnode_free_list_mtx);
881 mtx_unlock(&vnode_free_list_mtx);
882 vp = (struct vnode *) uma_zalloc(vnode_zone, M_WAITOK|M_ZERO);
886 vp->v_vnlock = &vp->v_lock;
887 mtx_init(&vp->v_interlock, "vnode interlock", NULL, MTX_DEF);
889 * By default, don't allow shared locks unless filesystems
892 lockinit(vp->v_vnlock, PVFS, tag, VLKTIMEOUT, LK_NOSHARE);
898 bo->bo_mtx = &vp->v_interlock;
899 bo->bo_ops = &buf_ops_bio;
901 TAILQ_INIT(&bo->bo_clean.bv_hd);
902 TAILQ_INIT(&bo->bo_dirty.bv_hd);
904 * Initialize namecache.
906 LIST_INIT(&vp->v_cache_src);
907 TAILQ_INIT(&vp->v_cache_dst);
909 * Finalize various vnode identity bits.
918 if (mp != NULL && (mp->mnt_flag & MNT_MULTILABEL) == 0)
919 mac_associate_vnode_singlelabel(mp, vp);
921 printf("NULL mp in getnewvnode()\n");
925 bo->bo_bsize = mp->mnt_stat.f_iosize;
926 if ((mp->mnt_kern_flag & MNTK_NOKNOTE) != 0)
927 vp->v_vflag |= VV_NOKNOTE;
930 CTR2(KTR_VFS, "getnewvnode: mp %p vp %p", mp, vp);
936 * Delete from old mount point vnode list, if on one.
939 delmntque(struct vnode *vp)
948 VNASSERT(mp->mnt_nvnodelistsize > 0, vp,
949 ("bad mount point vnode list size"));
950 TAILQ_REMOVE(&mp->mnt_nvnodelist, vp, v_nmntvnodes);
951 mp->mnt_nvnodelistsize--;
957 * Insert into list of vnodes for the new mount point, if available.
960 insmntque(struct vnode *vp, struct mount *mp)
964 VNASSERT(mp != NULL, vp, ("Don't call insmntque(foo, NULL)"));
967 TAILQ_INSERT_TAIL(&mp->mnt_nvnodelist, vp, v_nmntvnodes);
968 VNASSERT(mp->mnt_nvnodelistsize >= 0, vp,
969 ("neg mount point vnode list size"));
970 mp->mnt_nvnodelistsize++;
975 * Flush out and invalidate all buffers associated with a bufobj
976 * Called with the underlying object locked.
979 bufobj_invalbuf(struct bufobj *bo, int flags, struct thread *td, int slpflag,
985 if (flags & V_SAVE) {
986 error = bufobj_wwait(bo, slpflag, slptimeo);
991 if (bo->bo_dirty.bv_cnt > 0) {
993 if ((error = BO_SYNC(bo, MNT_WAIT, td)) != 0)
996 * XXX We could save a lock/unlock if this was only
997 * enabled under INVARIANTS
1000 if (bo->bo_numoutput > 0 || bo->bo_dirty.bv_cnt > 0)
1001 panic("vinvalbuf: dirty bufs");
1005 * If you alter this loop please notice that interlock is dropped and
1006 * reacquired in flushbuflist. Special care is needed to ensure that
1007 * no race conditions occur from this.
1010 error = flushbuflist(&bo->bo_clean,
1011 flags, bo, slpflag, slptimeo);
1013 error = flushbuflist(&bo->bo_dirty,
1014 flags, bo, slpflag, slptimeo);
1015 if (error != 0 && error != EAGAIN) {
1019 } while (error != 0);
1022 * Wait for I/O to complete. XXX needs cleaning up. The vnode can
1023 * have write I/O in-progress but if there is a VM object then the
1024 * VM object can also have read-I/O in-progress.
1027 bufobj_wwait(bo, 0, 0);
1029 if (bo->bo_object != NULL) {
1030 VM_OBJECT_LOCK(bo->bo_object);
1031 vm_object_pip_wait(bo->bo_object, "bovlbx");
1032 VM_OBJECT_UNLOCK(bo->bo_object);
1035 } while (bo->bo_numoutput > 0);
1039 * Destroy the copy in the VM cache, too.
1041 if (bo->bo_object != NULL) {
1042 VM_OBJECT_LOCK(bo->bo_object);
1043 vm_object_page_remove(bo->bo_object, 0, 0,
1044 (flags & V_SAVE) ? TRUE : FALSE);
1045 VM_OBJECT_UNLOCK(bo->bo_object);
1050 if ((flags & (V_ALT | V_NORMAL)) == 0 &&
1051 (bo->bo_dirty.bv_cnt > 0 || bo->bo_clean.bv_cnt > 0))
1052 panic("vinvalbuf: flush failed");
1059 * Flush out and invalidate all buffers associated with a vnode.
1060 * Called with the underlying object locked.
1063 vinvalbuf(struct vnode *vp, int flags, struct thread *td, int slpflag,
1067 CTR2(KTR_VFS, "vinvalbuf vp %p flags %d", vp, flags);
1068 ASSERT_VOP_LOCKED(vp, "vinvalbuf");
1069 return (bufobj_invalbuf(&vp->v_bufobj, flags, td, slpflag, slptimeo));
1073 * Flush out buffers on the specified list.
1077 flushbuflist( struct bufv *bufv, int flags, struct bufobj *bo, int slpflag,
1080 struct buf *bp, *nbp;
1085 ASSERT_BO_LOCKED(bo);
1088 TAILQ_FOREACH_SAFE(bp, &bufv->bv_hd, b_bobufs, nbp) {
1089 if (((flags & V_NORMAL) && (bp->b_xflags & BX_ALTDATA)) ||
1090 ((flags & V_ALT) && (bp->b_xflags & BX_ALTDATA) == 0)) {
1096 lblkno = nbp->b_lblkno;
1097 xflags = nbp->b_xflags &
1098 (BX_BKGRDMARKER | BX_VNDIRTY | BX_VNCLEAN);
1101 error = BUF_TIMELOCK(bp,
1102 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK, BO_MTX(bo),
1103 "flushbuf", slpflag, slptimeo);
1106 return (error != ENOLCK ? error : EAGAIN);
1108 KASSERT(bp->b_bufobj == bo,
1109 ("bp %p wrong b_bufobj %p should be %p",
1110 bp, bp->b_bufobj, bo));
1111 if (bp->b_bufobj != bo) { /* XXX: necessary ? */
1117 * XXX Since there are no node locks for NFS, I
1118 * believe there is a slight chance that a delayed
1119 * write will occur while sleeping just above, so
1122 if (((bp->b_flags & (B_DELWRI | B_INVAL)) == B_DELWRI) &&
1125 bp->b_flags |= B_ASYNC;
1128 return (EAGAIN); /* XXX: why not loop ? */
1131 bp->b_flags |= (B_INVAL | B_NOCACHE | B_RELBUF);
1132 bp->b_flags &= ~B_ASYNC;
1136 (nbp->b_bufobj != bo ||
1137 nbp->b_lblkno != lblkno ||
1139 (BX_BKGRDMARKER | BX_VNDIRTY | BX_VNCLEAN)) != xflags))
1140 break; /* nbp invalid */
1146 * Truncate a file's buffer and pages to a specified length. This
1147 * is in lieu of the old vinvalbuf mechanism, which performed unneeded
1151 vtruncbuf(struct vnode *vp, struct ucred *cred, struct thread *td,
1152 off_t length, int blksize)
1154 struct buf *bp, *nbp;
1159 CTR2(KTR_VFS, "vtruncbuf vp %p length %jd", vp, length);
1161 * Round up to the *next* lbn.
1163 trunclbn = (length + blksize - 1) / blksize;
1165 ASSERT_VOP_LOCKED(vp, "vtruncbuf");
1172 TAILQ_FOREACH_SAFE(bp, &bo->bo_clean.bv_hd, b_bobufs, nbp) {
1173 if (bp->b_lblkno < trunclbn)
1176 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK,
1177 VI_MTX(vp)) == ENOLCK)
1181 bp->b_flags |= (B_INVAL | B_RELBUF);
1182 bp->b_flags &= ~B_ASYNC;
1187 (((nbp->b_xflags & BX_VNCLEAN) == 0) ||
1188 (nbp->b_vp != vp) ||
1189 (nbp->b_flags & B_DELWRI))) {
1195 TAILQ_FOREACH_SAFE(bp, &bo->bo_dirty.bv_hd, b_bobufs, nbp) {
1196 if (bp->b_lblkno < trunclbn)
1199 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK,
1200 VI_MTX(vp)) == ENOLCK)
1203 bp->b_flags |= (B_INVAL | B_RELBUF);
1204 bp->b_flags &= ~B_ASYNC;
1208 (((nbp->b_xflags & BX_VNDIRTY) == 0) ||
1209 (nbp->b_vp != vp) ||
1210 (nbp->b_flags & B_DELWRI) == 0)) {
1219 TAILQ_FOREACH_SAFE(bp, &bo->bo_dirty.bv_hd, b_bobufs, nbp) {
1220 if (bp->b_lblkno > 0)
1223 * Since we hold the vnode lock this should only
1224 * fail if we're racing with the buf daemon.
1227 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK,
1228 VI_MTX(vp)) == ENOLCK) {
1231 VNASSERT((bp->b_flags & B_DELWRI), vp,
1232 ("buf(%p) on dirty queue without DELWRI", bp));
1241 bufobj_wwait(bo, 0, 0);
1243 vnode_pager_setsize(vp, length);
1249 * buf_splay() - splay tree core for the clean/dirty list of buffers in
1252 * NOTE: We have to deal with the special case of a background bitmap
1253 * buffer, a situation where two buffers will have the same logical
1254 * block offset. We want (1) only the foreground buffer to be accessed
1255 * in a lookup and (2) must differentiate between the foreground and
1256 * background buffer in the splay tree algorithm because the splay
1257 * tree cannot normally handle multiple entities with the same 'index'.
1258 * We accomplish this by adding differentiating flags to the splay tree's
1263 buf_splay(daddr_t lblkno, b_xflags_t xflags, struct buf *root)
1266 struct buf *lefttreemax, *righttreemin, *y;
1270 lefttreemax = righttreemin = &dummy;
1272 if (lblkno < root->b_lblkno ||
1273 (lblkno == root->b_lblkno &&
1274 (xflags & BX_BKGRDMARKER) < (root->b_xflags & BX_BKGRDMARKER))) {
1275 if ((y = root->b_left) == NULL)
1277 if (lblkno < y->b_lblkno) {
1279 root->b_left = y->b_right;
1282 if ((y = root->b_left) == NULL)
1285 /* Link into the new root's right tree. */
1286 righttreemin->b_left = root;
1287 righttreemin = root;
1288 } else if (lblkno > root->b_lblkno ||
1289 (lblkno == root->b_lblkno &&
1290 (xflags & BX_BKGRDMARKER) > (root->b_xflags & BX_BKGRDMARKER))) {
1291 if ((y = root->b_right) == NULL)
1293 if (lblkno > y->b_lblkno) {
1295 root->b_right = y->b_left;
1298 if ((y = root->b_right) == NULL)
1301 /* Link into the new root's left tree. */
1302 lefttreemax->b_right = root;
1309 /* Assemble the new root. */
1310 lefttreemax->b_right = root->b_left;
1311 righttreemin->b_left = root->b_right;
1312 root->b_left = dummy.b_right;
1313 root->b_right = dummy.b_left;
1318 buf_vlist_remove(struct buf *bp)
1323 KASSERT(bp->b_bufobj != NULL, ("No b_bufobj %p", bp));
1324 ASSERT_BO_LOCKED(bp->b_bufobj);
1325 KASSERT((bp->b_xflags & (BX_VNDIRTY|BX_VNCLEAN)) !=
1326 (BX_VNDIRTY|BX_VNCLEAN),
1327 ("buf_vlist_remove: Buf %p is on two lists", bp));
1328 if (bp->b_xflags & BX_VNDIRTY)
1329 bv = &bp->b_bufobj->bo_dirty;
1331 bv = &bp->b_bufobj->bo_clean;
1332 if (bp != bv->bv_root) {
1333 root = buf_splay(bp->b_lblkno, bp->b_xflags, bv->bv_root);
1334 KASSERT(root == bp, ("splay lookup failed in remove"));
1336 if (bp->b_left == NULL) {
1339 root = buf_splay(bp->b_lblkno, bp->b_xflags, bp->b_left);
1340 root->b_right = bp->b_right;
1343 TAILQ_REMOVE(&bv->bv_hd, bp, b_bobufs);
1345 bp->b_xflags &= ~(BX_VNDIRTY | BX_VNCLEAN);
1349 * Add the buffer to the sorted clean or dirty block list using a
1350 * splay tree algorithm.
1352 * NOTE: xflags is passed as a constant, optimizing this inline function!
1355 buf_vlist_add(struct buf *bp, struct bufobj *bo, b_xflags_t xflags)
1360 ASSERT_BO_LOCKED(bo);
1361 KASSERT((bp->b_xflags & (BX_VNDIRTY|BX_VNCLEAN)) == 0,
1362 ("buf_vlist_add: Buf %p has existing xflags %d", bp, bp->b_xflags));
1363 bp->b_xflags |= xflags;
1364 if (xflags & BX_VNDIRTY)
1369 root = buf_splay(bp->b_lblkno, bp->b_xflags, bv->bv_root);
1373 TAILQ_INSERT_TAIL(&bv->bv_hd, bp, b_bobufs);
1374 } else if (bp->b_lblkno < root->b_lblkno ||
1375 (bp->b_lblkno == root->b_lblkno &&
1376 (bp->b_xflags & BX_BKGRDMARKER) < (root->b_xflags & BX_BKGRDMARKER))) {
1377 bp->b_left = root->b_left;
1379 root->b_left = NULL;
1380 TAILQ_INSERT_BEFORE(root, bp, b_bobufs);
1382 bp->b_right = root->b_right;
1384 root->b_right = NULL;
1385 TAILQ_INSERT_AFTER(&bv->bv_hd, root, bp, b_bobufs);
1392 * Lookup a buffer using the splay tree. Note that we specifically avoid
1393 * shadow buffers used in background bitmap writes.
1395 * This code isn't quite efficient as it could be because we are maintaining
1396 * two sorted lists and do not know which list the block resides in.
1398 * During a "make buildworld" the desired buffer is found at one of
1399 * the roots more than 60% of the time. Thus, checking both roots
1400 * before performing either splay eliminates unnecessary splays on the
1401 * first tree splayed.
1404 gbincore(struct bufobj *bo, daddr_t lblkno)
1408 ASSERT_BO_LOCKED(bo);
1409 if ((bp = bo->bo_clean.bv_root) != NULL &&
1410 bp->b_lblkno == lblkno && !(bp->b_xflags & BX_BKGRDMARKER))
1412 if ((bp = bo->bo_dirty.bv_root) != NULL &&
1413 bp->b_lblkno == lblkno && !(bp->b_xflags & BX_BKGRDMARKER))
1415 if ((bp = bo->bo_clean.bv_root) != NULL) {
1416 bo->bo_clean.bv_root = bp = buf_splay(lblkno, 0, bp);
1417 if (bp->b_lblkno == lblkno && !(bp->b_xflags & BX_BKGRDMARKER))
1420 if ((bp = bo->bo_dirty.bv_root) != NULL) {
1421 bo->bo_dirty.bv_root = bp = buf_splay(lblkno, 0, bp);
1422 if (bp->b_lblkno == lblkno && !(bp->b_xflags & BX_BKGRDMARKER))
1429 * Associate a buffer with a vnode.
1432 bgetvp(struct vnode *vp, struct buf *bp)
1435 VNASSERT(bp->b_vp == NULL, bp->b_vp, ("bgetvp: not free"));
1437 CTR3(KTR_BUF, "bgetvp(%p) vp %p flags %X", bp, vp, bp->b_flags);
1438 VNASSERT((bp->b_xflags & (BX_VNDIRTY|BX_VNCLEAN)) == 0, vp,
1439 ("bgetvp: bp already attached! %p", bp));
1441 ASSERT_VI_LOCKED(vp, "bgetvp");
1444 bp->b_bufobj = &vp->v_bufobj;
1446 * Insert onto list for new vnode.
1448 buf_vlist_add(bp, &vp->v_bufobj, BX_VNCLEAN);
1452 * Disassociate a buffer from a vnode.
1455 brelvp(struct buf *bp)
1460 CTR3(KTR_BUF, "brelvp(%p) vp %p flags %X", bp, bp->b_vp, bp->b_flags);
1461 KASSERT(bp->b_vp != NULL, ("brelvp: NULL"));
1464 * Delete from old vnode list, if on one.
1466 vp = bp->b_vp; /* XXX */
1469 if (bp->b_xflags & (BX_VNDIRTY | BX_VNCLEAN))
1470 buf_vlist_remove(bp);
1472 panic("brelvp: Buffer %p not on queue.", bp);
1473 if ((bo->bo_flag & BO_ONWORKLST) && bo->bo_dirty.bv_cnt == 0) {
1474 bo->bo_flag &= ~BO_ONWORKLST;
1475 mtx_lock(&sync_mtx);
1476 LIST_REMOVE(bo, bo_synclist);
1477 syncer_worklist_len--;
1478 mtx_unlock(&sync_mtx);
1481 bp->b_bufobj = NULL;
1486 * Add an item to the syncer work queue.
1489 vn_syncer_add_to_worklist(struct bufobj *bo, int delay)
1493 ASSERT_BO_LOCKED(bo);
1495 mtx_lock(&sync_mtx);
1496 if (bo->bo_flag & BO_ONWORKLST)
1497 LIST_REMOVE(bo, bo_synclist);
1499 bo->bo_flag |= BO_ONWORKLST;
1500 syncer_worklist_len++;
1503 if (delay > syncer_maxdelay - 2)
1504 delay = syncer_maxdelay - 2;
1505 slot = (syncer_delayno + delay) & syncer_mask;
1507 LIST_INSERT_HEAD(&syncer_workitem_pending[slot], bo, bo_synclist);
1508 mtx_unlock(&sync_mtx);
1512 sysctl_vfs_worklist_len(SYSCTL_HANDLER_ARGS)
1516 mtx_lock(&sync_mtx);
1517 len = syncer_worklist_len - sync_vnode_count;
1518 mtx_unlock(&sync_mtx);
1519 error = SYSCTL_OUT(req, &len, sizeof(len));
1523 SYSCTL_PROC(_vfs, OID_AUTO, worklist_len, CTLTYPE_INT | CTLFLAG_RD, NULL, 0,
1524 sysctl_vfs_worklist_len, "I", "Syncer thread worklist length");
1526 static struct proc *updateproc;
1527 static void sched_sync(void);
1528 static struct kproc_desc up_kp = {
1533 SYSINIT(syncer, SI_SUB_KTHREAD_UPDATE, SI_ORDER_FIRST, kproc_start, &up_kp)
1536 sync_vnode(struct bufobj *bo, struct thread *td)
1541 vp = bo->__bo_vnode; /* XXX */
1542 if (VOP_ISLOCKED(vp, NULL) != 0)
1544 if (VI_TRYLOCK(vp) == 0)
1547 * We use vhold in case the vnode does not
1548 * successfully sync. vhold prevents the vnode from
1549 * going away when we unlock the sync_mtx so that
1550 * we can acquire the vnode interlock.
1553 mtx_unlock(&sync_mtx);
1555 if (vn_start_write(vp, &mp, V_NOWAIT) != 0) {
1557 mtx_lock(&sync_mtx);
1560 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, td);
1561 (void) VOP_FSYNC(vp, MNT_LAZY, td);
1562 VOP_UNLOCK(vp, 0, td);
1563 vn_finished_write(mp);
1565 if ((bo->bo_flag & BO_ONWORKLST) != 0) {
1567 * Put us back on the worklist. The worklist
1568 * routine will remove us from our current
1569 * position and then add us back in at a later
1572 vn_syncer_add_to_worklist(bo, syncdelay);
1575 mtx_lock(&sync_mtx);
1580 * System filesystem synchronizer daemon.
1585 struct synclist *next;
1586 struct synclist *slp;
1589 struct thread *td = FIRST_THREAD_IN_PROC(updateproc);
1590 static int dummychan;
1592 int net_worklist_len;
1593 int syncer_final_iter;
1599 syncer_final_iter = 0;
1601 syncer_state = SYNCER_RUNNING;
1602 starttime = time_uptime;
1603 td->td_pflags |= TDP_NORUNNINGBUF;
1605 EVENTHANDLER_REGISTER(shutdown_pre_sync, syncer_shutdown, td->td_proc,
1609 mtx_lock(&sync_mtx);
1610 if (syncer_state == SYNCER_FINAL_DELAY &&
1611 syncer_final_iter == 0) {
1612 mtx_unlock(&sync_mtx);
1613 kthread_suspend_check(td->td_proc);
1614 mtx_lock(&sync_mtx);
1616 net_worklist_len = syncer_worklist_len - sync_vnode_count;
1617 if (syncer_state != SYNCER_RUNNING &&
1618 starttime != time_uptime) {
1620 printf("\nSyncing disks, vnodes remaining...");
1623 printf("%d ", net_worklist_len);
1625 starttime = time_uptime;
1628 * Push files whose dirty time has expired. Be careful
1629 * of interrupt race on slp queue.
1631 * Skip over empty worklist slots when shutting down.
1634 slp = &syncer_workitem_pending[syncer_delayno];
1635 syncer_delayno += 1;
1636 if (syncer_delayno == syncer_maxdelay)
1638 next = &syncer_workitem_pending[syncer_delayno];
1640 * If the worklist has wrapped since the
1641 * it was emptied of all but syncer vnodes,
1642 * switch to the FINAL_DELAY state and run
1643 * for one more second.
1645 if (syncer_state == SYNCER_SHUTTING_DOWN &&
1646 net_worklist_len == 0 &&
1647 last_work_seen == syncer_delayno) {
1648 syncer_state = SYNCER_FINAL_DELAY;
1649 syncer_final_iter = SYNCER_SHUTDOWN_SPEEDUP;
1651 } while (syncer_state != SYNCER_RUNNING && LIST_EMPTY(slp) &&
1652 syncer_worklist_len > 0);
1655 * Keep track of the last time there was anything
1656 * on the worklist other than syncer vnodes.
1657 * Return to the SHUTTING_DOWN state if any
1660 if (net_worklist_len > 0 || syncer_state == SYNCER_RUNNING)
1661 last_work_seen = syncer_delayno;
1662 if (net_worklist_len > 0 && syncer_state == SYNCER_FINAL_DELAY)
1663 syncer_state = SYNCER_SHUTTING_DOWN;
1664 while ((bo = LIST_FIRST(slp)) != NULL) {
1665 error = sync_vnode(bo, td);
1667 LIST_REMOVE(bo, bo_synclist);
1668 LIST_INSERT_HEAD(next, bo, bo_synclist);
1672 if (syncer_state == SYNCER_FINAL_DELAY && syncer_final_iter > 0)
1673 syncer_final_iter--;
1674 mtx_unlock(&sync_mtx);
1676 * The variable rushjob allows the kernel to speed up the
1677 * processing of the filesystem syncer process. A rushjob
1678 * value of N tells the filesystem syncer to process the next
1679 * N seconds worth of work on its queue ASAP. Currently rushjob
1680 * is used by the soft update code to speed up the filesystem
1681 * syncer process when the incore state is getting so far
1682 * ahead of the disk that the kernel memory pool is being
1683 * threatened with exhaustion.
1685 mtx_lock(&sync_mtx);
1688 mtx_unlock(&sync_mtx);
1691 mtx_unlock(&sync_mtx);
1693 * Just sleep for a short period if time between
1694 * iterations when shutting down to allow some I/O
1697 * If it has taken us less than a second to process the
1698 * current work, then wait. Otherwise start right over
1699 * again. We can still lose time if any single round
1700 * takes more than two seconds, but it does not really
1701 * matter as we are just trying to generally pace the
1702 * filesystem activity.
1704 if (syncer_state != SYNCER_RUNNING)
1705 tsleep(&dummychan, PPAUSE, "syncfnl",
1706 hz / SYNCER_SHUTDOWN_SPEEDUP);
1707 else if (time_uptime == starttime)
1708 tsleep(&lbolt, PPAUSE, "syncer", 0);
1713 * Request the syncer daemon to speed up its work.
1714 * We never push it to speed up more than half of its
1715 * normal turn time, otherwise it could take over the cpu.
1723 td = FIRST_THREAD_IN_PROC(updateproc);
1724 sleepq_remove(td, &lbolt);
1725 mtx_lock(&sync_mtx);
1726 if (rushjob < syncdelay / 2) {
1728 stat_rush_requests += 1;
1731 mtx_unlock(&sync_mtx);
1736 * Tell the syncer to speed up its work and run though its work
1737 * list several times, then tell it to shut down.
1740 syncer_shutdown(void *arg, int howto)
1744 if (howto & RB_NOSYNC)
1746 td = FIRST_THREAD_IN_PROC(updateproc);
1747 sleepq_remove(td, &lbolt);
1748 mtx_lock(&sync_mtx);
1749 syncer_state = SYNCER_SHUTTING_DOWN;
1751 mtx_unlock(&sync_mtx);
1752 kproc_shutdown(arg, howto);
1756 * Reassign a buffer from one vnode to another.
1757 * Used to assign file specific control information
1758 * (indirect blocks) to the vnode to which they belong.
1761 reassignbuf(struct buf *bp)
1774 CTR3(KTR_BUF, "reassignbuf(%p) vp %p flags %X",
1775 bp, bp->b_vp, bp->b_flags);
1777 * B_PAGING flagged buffers cannot be reassigned because their vp
1778 * is not fully linked in.
1780 if (bp->b_flags & B_PAGING)
1781 panic("cannot reassign paging buffer");
1784 * Delete from old vnode list, if on one.
1787 if (bp->b_xflags & (BX_VNDIRTY | BX_VNCLEAN))
1788 buf_vlist_remove(bp);
1790 panic("reassignbuf: Buffer %p not on queue.", bp);
1792 * If dirty, put on list of dirty buffers; otherwise insert onto list
1795 if (bp->b_flags & B_DELWRI) {
1796 if ((bo->bo_flag & BO_ONWORKLST) == 0) {
1797 switch (vp->v_type) {
1807 vn_syncer_add_to_worklist(bo, delay);
1809 buf_vlist_add(bp, bo, BX_VNDIRTY);
1811 buf_vlist_add(bp, bo, BX_VNCLEAN);
1813 if ((bo->bo_flag & BO_ONWORKLST) && bo->bo_dirty.bv_cnt == 0) {
1814 mtx_lock(&sync_mtx);
1815 LIST_REMOVE(bo, bo_synclist);
1816 syncer_worklist_len--;
1817 mtx_unlock(&sync_mtx);
1818 bo->bo_flag &= ~BO_ONWORKLST;
1823 bp = TAILQ_FIRST(&bv->bv_hd);
1824 KASSERT(bp == NULL || bp->b_bufobj == bo,
1825 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo));
1826 bp = TAILQ_LAST(&bv->bv_hd, buflists);
1827 KASSERT(bp == NULL || bp->b_bufobj == bo,
1828 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo));
1830 bp = TAILQ_FIRST(&bv->bv_hd);
1831 KASSERT(bp == NULL || bp->b_bufobj == bo,
1832 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo));
1833 bp = TAILQ_LAST(&bv->bv_hd, buflists);
1834 KASSERT(bp == NULL || bp->b_bufobj == bo,
1835 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo));
1841 * Increment the use and hold counts on the vnode, taking care to reference
1842 * the driver's usecount if this is a chardev. The vholdl() will remove
1843 * the vnode from the free list if it is presently free. Requires the
1844 * vnode interlock and returns with it held.
1847 v_incr_usecount(struct vnode *vp)
1850 CTR3(KTR_VFS, "v_incr_usecount: vp %p holdcnt %d usecount %d\n",
1851 vp, vp->v_holdcnt, vp->v_usecount);
1853 if (vp->v_type == VCHR && vp->v_rdev != NULL) {
1855 vp->v_rdev->si_usecount++;
1862 * Turn a holdcnt into a use+holdcnt such that only one call to
1863 * v_decr_usecount is needed.
1866 v_upgrade_usecount(struct vnode *vp)
1869 CTR3(KTR_VFS, "v_upgrade_usecount: vp %p holdcnt %d usecount %d\n",
1870 vp, vp->v_holdcnt, vp->v_usecount);
1872 if (vp->v_type == VCHR && vp->v_rdev != NULL) {
1874 vp->v_rdev->si_usecount++;
1880 * Decrement the vnode use and hold count along with the driver's usecount
1881 * if this is a chardev. The vdropl() below releases the vnode interlock
1882 * as it may free the vnode.
1885 v_decr_usecount(struct vnode *vp)
1888 CTR3(KTR_VFS, "v_decr_usecount: vp %p holdcnt %d usecount %d\n",
1889 vp, vp->v_holdcnt, vp->v_usecount);
1890 ASSERT_VI_LOCKED(vp, __FUNCTION__);
1891 VNASSERT(vp->v_usecount > 0, vp,
1892 ("v_decr_usecount: negative usecount"));
1894 if (vp->v_type == VCHR && vp->v_rdev != NULL) {
1896 vp->v_rdev->si_usecount--;
1903 * Decrement only the use count and driver use count. This is intended to
1904 * be paired with a follow on vdropl() to release the remaining hold count.
1905 * In this way we may vgone() a vnode with a 0 usecount without risk of
1906 * having it end up on a free list because the hold count is kept above 0.
1909 v_decr_useonly(struct vnode *vp)
1912 CTR3(KTR_VFS, "v_decr_useonly: vp %p holdcnt %d usecount %d\n",
1913 vp, vp->v_holdcnt, vp->v_usecount);
1914 ASSERT_VI_LOCKED(vp, __FUNCTION__);
1915 VNASSERT(vp->v_usecount > 0, vp,
1916 ("v_decr_useonly: negative usecount"));
1918 if (vp->v_type == VCHR && vp->v_rdev != NULL) {
1920 vp->v_rdev->si_usecount--;
1926 * Grab a particular vnode from the free list, increment its
1927 * reference count and lock it. The vnode lock bit is set if the
1928 * vnode is being eliminated in vgone. The process is awakened
1929 * when the transition is completed, and an error returned to
1930 * indicate that the vnode is no longer usable (possibly having
1931 * been changed to a new filesystem type).
1934 vget(struct vnode *vp, int flags, struct thread *td)
1943 VFS_ASSERT_GIANT(vp->v_mount);
1944 if ((flags & LK_INTERLOCK) == 0)
1947 * If the inactive call was deferred because vput() was called
1948 * with a shared lock, we have to do it here before another thread
1949 * gets a reference to data that should be dead.
1951 if (vp->v_iflag & VI_OWEINACT) {
1952 if (flags & LK_NOWAIT) {
1956 flags &= ~LK_TYPE_MASK;
1957 flags |= LK_EXCLUSIVE;
1961 if ((error = vn_lock(vp, flags | LK_INTERLOCK, td)) != 0) {
1966 /* Upgrade our holdcnt to a usecount. */
1967 v_upgrade_usecount(vp);
1968 if (vp->v_iflag & VI_DOOMED && (flags & LK_RETRY) == 0)
1969 panic("vget: vn_lock failed to return ENOENT\n");
1971 if (vp->v_iflag & VI_OWEINACT)
1974 if ((oldflags & LK_TYPE_MASK) == 0)
1975 VOP_UNLOCK(vp, 0, td);
1982 * Increase the reference count of a vnode.
1985 vref(struct vnode *vp)
1989 v_incr_usecount(vp);
1994 * Return reference count of a vnode.
1996 * The results of this call are only guaranteed when some mechanism other
1997 * than the VI lock is used to stop other processes from gaining references
1998 * to the vnode. This may be the case if the caller holds the only reference.
1999 * This is also useful when stale data is acceptable as race conditions may
2000 * be accounted for by some other means.
2003 vrefcnt(struct vnode *vp)
2008 usecnt = vp->v_usecount;
2016 * Vnode put/release.
2017 * If count drops to zero, call inactive routine and return to freelist.
2020 vrele(struct vnode *vp)
2022 struct thread *td = curthread; /* XXX */
2024 KASSERT(vp != NULL, ("vrele: null vp"));
2025 VFS_ASSERT_GIANT(vp->v_mount);
2029 /* Skip this v_writecount check if we're going to panic below. */
2030 VNASSERT(vp->v_writecount < vp->v_usecount || vp->v_usecount < 1, vp,
2031 ("vrele: missed vn_close"));
2033 if (vp->v_usecount > 1 || ((vp->v_iflag & VI_DOINGINACT) &&
2034 vp->v_usecount == 1)) {
2035 v_decr_usecount(vp);
2038 if (vp->v_usecount != 1) {
2040 vprint("vrele: negative ref count", vp);
2043 panic("vrele: negative ref cnt");
2046 * We want to hold the vnode until the inactive finishes to
2047 * prevent vgone() races. We drop the use count here and the
2048 * hold count below when we're done.
2052 * We must call VOP_INACTIVE with the node locked. Mark
2053 * as VI_DOINGINACT to avoid recursion.
2055 if (vn_lock(vp, LK_EXCLUSIVE | LK_INTERLOCK, td) == 0) {
2058 VOP_UNLOCK(vp, 0, td);
2065 * Release an already locked vnode. This give the same effects as
2066 * unlock+vrele(), but takes less time and avoids releasing and
2067 * re-aquiring the lock (as vrele() aquires the lock internally.)
2070 vput(struct vnode *vp)
2072 struct thread *td = curthread; /* XXX */
2075 KASSERT(vp != NULL, ("vput: null vp"));
2076 ASSERT_VOP_LOCKED(vp, "vput");
2077 VFS_ASSERT_GIANT(vp->v_mount);
2079 /* Skip this v_writecount check if we're going to panic below. */
2080 VNASSERT(vp->v_writecount < vp->v_usecount || vp->v_usecount < 1, vp,
2081 ("vput: missed vn_close"));
2084 if (vp->v_usecount > 1 || ((vp->v_iflag & VI_DOINGINACT) &&
2085 vp->v_usecount == 1)) {
2086 VOP_UNLOCK(vp, 0, td);
2087 v_decr_usecount(vp);
2091 if (vp->v_usecount != 1) {
2093 vprint("vput: negative ref count", vp);
2095 panic("vput: negative ref cnt");
2098 * We want to hold the vnode until the inactive finishes to
2099 * prevent vgone() races. We drop the use count here and the
2100 * hold count below when we're done.
2103 vp->v_iflag |= VI_OWEINACT;
2104 if (VOP_ISLOCKED(vp, NULL) != LK_EXCLUSIVE) {
2105 error = VOP_LOCK(vp, LK_EXCLUPGRADE|LK_INTERLOCK|LK_NOWAIT, td);
2110 if (vp->v_iflag & VI_OWEINACT)
2112 VOP_UNLOCK(vp, 0, td);
2118 * Somebody doesn't want the vnode recycled.
2121 vhold(struct vnode *vp)
2130 vholdl(struct vnode *vp)
2134 if (VSHOULDBUSY(vp))
2139 * Note that there is one less who cares about this vnode. vdrop() is the
2140 * opposite of vhold().
2143 vdrop(struct vnode *vp)
2151 * Drop the hold count of the vnode. If this is the last reference to
2152 * the vnode we will free it if it has been vgone'd otherwise it is
2153 * placed on the free list.
2156 vdropl(struct vnode *vp)
2159 if (vp->v_holdcnt <= 0)
2160 panic("vdrop: holdcnt %d", vp->v_holdcnt);
2162 if (vp->v_holdcnt == 0) {
2163 if (vp->v_iflag & VI_DOOMED) {
2173 * Call VOP_INACTIVE on the vnode and manage the DOINGINACT and OWEINACT
2174 * flags. DOINGINACT prevents us from recursing in calls to vinactive.
2175 * OWEINACT tracks whether a vnode missed a call to inactive due to a
2176 * failed lock upgrade.
2179 vinactive(struct vnode *vp, struct thread *td)
2182 ASSERT_VOP_LOCKED(vp, "vinactive");
2183 ASSERT_VI_LOCKED(vp, "vinactive");
2184 VNASSERT((vp->v_iflag & VI_DOINGINACT) == 0, vp,
2185 ("vinactive: recursed on VI_DOINGINACT"));
2186 vp->v_iflag |= VI_DOINGINACT;
2187 vp->v_iflag &= ~VI_OWEINACT;
2189 VOP_INACTIVE(vp, td);
2191 VNASSERT(vp->v_iflag & VI_DOINGINACT, vp,
2192 ("vinactive: lost VI_DOINGINACT"));
2193 vp->v_iflag &= ~VI_DOINGINACT;
2197 * Remove any vnodes in the vnode table belonging to mount point mp.
2199 * If FORCECLOSE is not specified, there should not be any active ones,
2200 * return error if any are found (nb: this is a user error, not a
2201 * system error). If FORCECLOSE is specified, detach any active vnodes
2204 * If WRITECLOSE is set, only flush out regular file vnodes open for
2207 * SKIPSYSTEM causes any vnodes marked VV_SYSTEM to be skipped.
2209 * `rootrefs' specifies the base reference count for the root vnode
2210 * of this filesystem. The root vnode is considered busy if its
2211 * v_usecount exceeds this value. On a successful return, vflush(, td)
2212 * will call vrele() on the root vnode exactly rootrefs times.
2213 * If the SKIPSYSTEM or WRITECLOSE flags are specified, rootrefs must
2217 static int busyprt = 0; /* print out busy vnodes */
2218 SYSCTL_INT(_debug, OID_AUTO, busyprt, CTLFLAG_RW, &busyprt, 0, "");
2222 vflush( struct mount *mp, int rootrefs, int flags, struct thread *td)
2224 struct vnode *vp, *mvp, *rootvp = NULL;
2226 int busy = 0, error;
2228 CTR1(KTR_VFS, "vflush: mp %p", mp);
2230 KASSERT((flags & (SKIPSYSTEM | WRITECLOSE)) == 0,
2231 ("vflush: bad args"));
2233 * Get the filesystem root vnode. We can vput() it
2234 * immediately, since with rootrefs > 0, it won't go away.
2236 if ((error = VFS_ROOT(mp, LK_EXCLUSIVE, &rootvp, td)) != 0)
2243 MNT_VNODE_FOREACH(vp, mp, mvp) {
2248 error = vn_lock(vp, LK_INTERLOCK | LK_EXCLUSIVE, td);
2252 MNT_VNODE_FOREACH_ABORT_ILOCKED(mp, mvp);
2256 * Skip over a vnodes marked VV_SYSTEM.
2258 if ((flags & SKIPSYSTEM) && (vp->v_vflag & VV_SYSTEM)) {
2259 VOP_UNLOCK(vp, 0, td);
2265 * If WRITECLOSE is set, flush out unlinked but still open
2266 * files (even if open only for reading) and regular file
2267 * vnodes open for writing.
2269 if (flags & WRITECLOSE) {
2270 error = VOP_GETATTR(vp, &vattr, td->td_ucred, td);
2273 if ((vp->v_type == VNON ||
2274 (error == 0 && vattr.va_nlink > 0)) &&
2275 (vp->v_writecount == 0 || vp->v_type != VREG)) {
2276 VOP_UNLOCK(vp, 0, td);
2284 * With v_usecount == 0, all we need to do is clear out the
2285 * vnode data structures and we are done.
2287 * If FORCECLOSE is set, forcibly close the vnode.
2289 if (vp->v_usecount == 0 || (flags & FORCECLOSE)) {
2290 VNASSERT(vp->v_usecount == 0 ||
2291 (vp->v_type != VCHR && vp->v_type != VBLK), vp,
2292 ("device VNODE %p is FORCECLOSED", vp));
2298 vprint("vflush: busy vnode", vp);
2301 VOP_UNLOCK(vp, 0, td);
2306 if (rootrefs > 0 && (flags & FORCECLOSE) == 0) {
2308 * If just the root vnode is busy, and if its refcount
2309 * is equal to `rootrefs', then go ahead and kill it.
2312 KASSERT(busy > 0, ("vflush: not busy"));
2313 VNASSERT(rootvp->v_usecount >= rootrefs, rootvp,
2314 ("vflush: usecount %d < rootrefs %d",
2315 rootvp->v_usecount, rootrefs));
2316 if (busy == 1 && rootvp->v_usecount == rootrefs) {
2317 VOP_LOCK(rootvp, LK_EXCLUSIVE|LK_INTERLOCK, td);
2319 VOP_UNLOCK(rootvp, 0, td);
2326 for (; rootrefs > 0; rootrefs--)
2332 * Recycle an unused vnode to the front of the free list.
2335 vrecycle(struct vnode *vp, struct thread *td)
2339 ASSERT_VOP_LOCKED(vp, "vrecycle");
2342 if (vp->v_usecount == 0) {
2351 * Eliminate all activity associated with a vnode
2352 * in preparation for reuse.
2355 vgone(struct vnode *vp)
2363 * vgone, with the vp interlock held.
2366 vgonel(struct vnode *vp)
2372 CTR1(KTR_VFS, "vgonel: vp %p", vp);
2373 ASSERT_VOP_LOCKED(vp, "vgonel");
2374 ASSERT_VI_LOCKED(vp, "vgonel");
2376 /* XXX Need to fix ttyvp before I enable this. */
2377 VNASSERT(vp->v_holdcnt, vp,
2378 ("vgonel: vp %p has no reference.", vp));
2383 * Don't vgonel if we're already doomed.
2385 if (vp->v_iflag & VI_DOOMED)
2387 vp->v_iflag |= VI_DOOMED;
2389 * Check to see if the vnode is in use. If so, we have to call
2390 * VOP_CLOSE() and VOP_INACTIVE().
2392 active = vp->v_usecount;
2393 oweinact = (vp->v_iflag & VI_OWEINACT);
2396 * Clean out any buffers associated with the vnode.
2397 * If the flush fails, just toss the buffers.
2399 if (!TAILQ_EMPTY(&vp->v_bufobj.bo_dirty.bv_hd))
2400 (void) vn_write_suspend_wait(vp, NULL, V_WAIT);
2401 if (vinvalbuf(vp, V_SAVE, td, 0, 0) != 0)
2402 vinvalbuf(vp, 0, td, 0, 0);
2405 * If purging an active vnode, it must be closed and
2406 * deactivated before being reclaimed.
2409 VOP_CLOSE(vp, FNONBLOCK, NOCRED, td);
2410 if (oweinact || active) {
2412 if ((vp->v_iflag & VI_DOINGINACT) == 0)
2417 * Reclaim the vnode.
2419 if (VOP_RECLAIM(vp, td))
2420 panic("vgone: cannot reclaim");
2421 VNASSERT(vp->v_object == NULL, vp,
2422 ("vop_reclaim left v_object vp=%p, tag=%s", vp, vp->v_tag));
2424 * Delete from old mount point vnode list.
2429 * Done with purge, reset to the standard lock and invalidate
2433 vp->v_vnlock = &vp->v_lock;
2434 vp->v_op = &dead_vnodeops;
2440 * Calculate the total number of references to a special device.
2443 vcount(struct vnode *vp)
2448 count = vp->v_rdev->si_usecount;
2454 * Same as above, but using the struct cdev *as argument
2457 count_dev(struct cdev *dev)
2462 count = dev->si_usecount;
2468 * Print out a description of a vnode.
2470 static char *typename[] =
2471 {"VNON", "VREG", "VDIR", "VBLK", "VCHR", "VLNK", "VSOCK", "VFIFO", "VBAD",
2475 vn_printf(struct vnode *vp, const char *fmt, ...)
2483 printf("%p: ", (void *)vp);
2484 printf("tag %s, type %s\n", vp->v_tag, typename[vp->v_type]);
2485 printf(" usecount %d, writecount %d, refcount %d mountedhere %p\n",
2486 vp->v_usecount, vp->v_writecount, vp->v_holdcnt, vp->v_mountedhere);
2489 if (vp->v_vflag & VV_ROOT)
2490 strcat(buf, "|VV_ROOT");
2491 if (vp->v_vflag & VV_TEXT)
2492 strcat(buf, "|VV_TEXT");
2493 if (vp->v_vflag & VV_SYSTEM)
2494 strcat(buf, "|VV_SYSTEM");
2495 if (vp->v_iflag & VI_DOOMED)
2496 strcat(buf, "|VI_DOOMED");
2497 if (vp->v_iflag & VI_FREE)
2498 strcat(buf, "|VI_FREE");
2499 printf(" flags (%s)\n", buf + 1);
2500 if (mtx_owned(VI_MTX(vp)))
2501 printf(" VI_LOCKed");
2502 if (vp->v_object != NULL)
2503 printf(" v_object %p ref %d pages %d\n",
2504 vp->v_object, vp->v_object->ref_count,
2505 vp->v_object->resident_page_count);
2507 lockmgr_printinfo(vp->v_vnlock);
2509 if (vp->v_data != NULL)
2514 #include <ddb/ddb.h>
2516 * List all of the locked vnodes in the system.
2517 * Called when debugging the kernel.
2519 DB_SHOW_COMMAND(lockedvnods, lockedvnodes)
2521 struct mount *mp, *nmp;
2525 * Note: because this is DDB, we can't obey the locking semantics
2526 * for these structures, which means we could catch an inconsistent
2527 * state and dereference a nasty pointer. Not much to be done
2530 printf("Locked vnodes\n");
2531 for (mp = TAILQ_FIRST(&mountlist); mp != NULL; mp = nmp) {
2532 nmp = TAILQ_NEXT(mp, mnt_list);
2533 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) {
2534 if (vp->v_type != VMARKER && VOP_ISLOCKED(vp, NULL))
2537 nmp = TAILQ_NEXT(mp, mnt_list);
2543 * Fill in a struct xvfsconf based on a struct vfsconf.
2546 vfsconf2x(struct vfsconf *vfsp, struct xvfsconf *xvfsp)
2549 strcpy(xvfsp->vfc_name, vfsp->vfc_name);
2550 xvfsp->vfc_typenum = vfsp->vfc_typenum;
2551 xvfsp->vfc_refcount = vfsp->vfc_refcount;
2552 xvfsp->vfc_flags = vfsp->vfc_flags;
2554 * These are unused in userland, we keep them
2555 * to not break binary compatibility.
2557 xvfsp->vfc_vfsops = NULL;
2558 xvfsp->vfc_next = NULL;
2562 * Top level filesystem related information gathering.
2565 sysctl_vfs_conflist(SYSCTL_HANDLER_ARGS)
2567 struct vfsconf *vfsp;
2568 struct xvfsconf xvfsp;
2572 TAILQ_FOREACH(vfsp, &vfsconf, vfc_list) {
2573 bzero(&xvfsp, sizeof(xvfsp));
2574 vfsconf2x(vfsp, &xvfsp);
2575 error = SYSCTL_OUT(req, &xvfsp, sizeof xvfsp);
2582 SYSCTL_PROC(_vfs, OID_AUTO, conflist, CTLFLAG_RD, NULL, 0, sysctl_vfs_conflist,
2583 "S,xvfsconf", "List of all configured filesystems");
2585 #ifndef BURN_BRIDGES
2586 static int sysctl_ovfs_conf(SYSCTL_HANDLER_ARGS);
2589 vfs_sysctl(SYSCTL_HANDLER_ARGS)
2591 int *name = (int *)arg1 - 1; /* XXX */
2592 u_int namelen = arg2 + 1; /* XXX */
2593 struct vfsconf *vfsp;
2594 struct xvfsconf xvfsp;
2596 printf("WARNING: userland calling deprecated sysctl, "
2597 "please rebuild world\n");
2599 #if 1 || defined(COMPAT_PRELITE2)
2600 /* Resolve ambiguity between VFS_VFSCONF and VFS_GENERIC. */
2602 return (sysctl_ovfs_conf(oidp, arg1, arg2, req));
2606 case VFS_MAXTYPENUM:
2609 return (SYSCTL_OUT(req, &maxvfsconf, sizeof(int)));
2612 return (ENOTDIR); /* overloaded */
2613 TAILQ_FOREACH(vfsp, &vfsconf, vfc_list)
2614 if (vfsp->vfc_typenum == name[2])
2617 return (EOPNOTSUPP);
2618 bzero(&xvfsp, sizeof(xvfsp));
2619 vfsconf2x(vfsp, &xvfsp);
2620 return (SYSCTL_OUT(req, &xvfsp, sizeof(xvfsp)));
2622 return (EOPNOTSUPP);
2625 static SYSCTL_NODE(_vfs, VFS_GENERIC, generic, CTLFLAG_RD | CTLFLAG_SKIP,
2626 vfs_sysctl, "Generic filesystem");
2628 #if 1 || defined(COMPAT_PRELITE2)
2631 sysctl_ovfs_conf(SYSCTL_HANDLER_ARGS)
2634 struct vfsconf *vfsp;
2635 struct ovfsconf ovfs;
2637 TAILQ_FOREACH(vfsp, &vfsconf, vfc_list) {
2638 bzero(&ovfs, sizeof(ovfs));
2639 ovfs.vfc_vfsops = vfsp->vfc_vfsops; /* XXX used as flag */
2640 strcpy(ovfs.vfc_name, vfsp->vfc_name);
2641 ovfs.vfc_index = vfsp->vfc_typenum;
2642 ovfs.vfc_refcount = vfsp->vfc_refcount;
2643 ovfs.vfc_flags = vfsp->vfc_flags;
2644 error = SYSCTL_OUT(req, &ovfs, sizeof ovfs);
2651 #endif /* 1 || COMPAT_PRELITE2 */
2652 #endif /* !BURN_BRIDGES */
2654 #define KINFO_VNODESLOP 10
2657 * Dump vnode list (via sysctl).
2661 sysctl_vnode(SYSCTL_HANDLER_ARGS)
2664 struct thread *td = req->td;
2670 * Stale numvnodes access is not fatal here.
2673 len = (numvnodes + KINFO_VNODESLOP) * sizeof *xvn;
2675 /* Make an estimate */
2676 return (SYSCTL_OUT(req, 0, len));
2678 error = sysctl_wire_old_buffer(req, 0);
2681 xvn = malloc(len, M_TEMP, M_ZERO | M_WAITOK);
2683 mtx_lock(&mountlist_mtx);
2684 TAILQ_FOREACH(mp, &mountlist, mnt_list) {
2685 if (vfs_busy(mp, LK_NOWAIT, &mountlist_mtx, td))
2688 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) {
2692 xvn[n].xv_size = sizeof *xvn;
2693 xvn[n].xv_vnode = vp;
2694 xvn[n].xv_id = 0; /* XXX compat */
2695 #define XV_COPY(field) xvn[n].xv_##field = vp->v_##field
2697 XV_COPY(writecount);
2703 xvn[n].xv_flag = vp->v_vflag;
2705 switch (vp->v_type) {
2712 if (vp->v_rdev == NULL) {
2716 xvn[n].xv_dev = dev2udev(vp->v_rdev);
2719 xvn[n].xv_socket = vp->v_socket;
2722 xvn[n].xv_fifo = vp->v_fifoinfo;
2727 /* shouldn't happen? */
2735 mtx_lock(&mountlist_mtx);
2740 mtx_unlock(&mountlist_mtx);
2742 error = SYSCTL_OUT(req, xvn, n * sizeof *xvn);
2747 SYSCTL_PROC(_kern, KERN_VNODE, vnode, CTLTYPE_OPAQUE|CTLFLAG_RD,
2748 0, 0, sysctl_vnode, "S,xvnode", "");
2752 * Unmount all filesystems. The list is traversed in reverse order
2753 * of mounting to avoid dependencies.
2756 vfs_unmountall(void)
2762 KASSERT(curthread != NULL, ("vfs_unmountall: NULL curthread"));
2765 * Since this only runs when rebooting, it is not interlocked.
2767 while(!TAILQ_EMPTY(&mountlist)) {
2768 mp = TAILQ_LAST(&mountlist, mntlist);
2769 error = dounmount(mp, MNT_FORCE, td);
2771 TAILQ_REMOVE(&mountlist, mp, mnt_list);
2773 * XXX: Due to the way in which we mount the root
2774 * file system off of devfs, devfs will generate a
2775 * "busy" warning when we try to unmount it before
2776 * the root. Don't print a warning as a result in
2777 * order to avoid false positive errors that may
2778 * cause needless upset.
2780 if (strcmp(mp->mnt_vfc->vfc_name, "devfs") != 0) {
2781 printf("unmount of %s failed (",
2782 mp->mnt_stat.f_mntonname);
2786 printf("%d)\n", error);
2789 /* The unmount has removed mp from the mountlist */
2795 * perform msync on all vnodes under a mount point
2796 * the mount point must be locked.
2799 vfs_msync(struct mount *mp, int flags)
2801 struct vnode *vp, *mvp;
2802 struct vm_object *obj;
2804 (void) vn_start_write(NULL, &mp, V_WAIT);
2806 MNT_VNODE_FOREACH(vp, mp, mvp) {
2808 if ((vp->v_iflag & VI_OBJDIRTY) &&
2809 (flags == MNT_WAIT || VOP_ISLOCKED(vp, NULL) == 0)) {
2812 LK_EXCLUSIVE | LK_RETRY | LK_INTERLOCK,
2814 if (vp->v_vflag & VV_NOSYNC) { /* unlinked */
2822 VM_OBJECT_LOCK(obj);
2823 vm_object_page_clean(obj, 0, 0,
2825 OBJPC_SYNC : OBJPC_NOSYNC);
2826 VM_OBJECT_UNLOCK(obj);
2835 vn_finished_write(mp);
2839 * Mark a vnode as free, putting it up for recycling.
2842 vfree(struct vnode *vp)
2845 CTR1(KTR_VFS, "vfree vp %p", vp);
2846 ASSERT_VI_LOCKED(vp, "vfree");
2847 mtx_lock(&vnode_free_list_mtx);
2848 VNASSERT(vp->v_op != NULL, vp, ("vfree: vnode already reclaimed."));
2849 VNASSERT((vp->v_iflag & VI_FREE) == 0, vp, ("vnode already free"));
2850 VNASSERT(VSHOULDFREE(vp), vp, ("vfree: freeing when we shouldn't"));
2851 VNASSERT((vp->v_iflag & VI_DOOMED) == 0, vp,
2852 ("vfree: Freeing doomed vnode"));
2853 if (vp->v_iflag & VI_AGE) {
2854 TAILQ_INSERT_HEAD(&vnode_free_list, vp, v_freelist);
2856 TAILQ_INSERT_TAIL(&vnode_free_list, vp, v_freelist);
2859 vp->v_iflag &= ~VI_AGE;
2860 vp->v_iflag |= VI_FREE;
2861 mtx_unlock(&vnode_free_list_mtx);
2865 * Opposite of vfree() - mark a vnode as in use.
2868 vbusy(struct vnode *vp)
2870 CTR1(KTR_VFS, "vbusy vp %p", vp);
2871 ASSERT_VI_LOCKED(vp, "vbusy");
2872 VNASSERT((vp->v_iflag & VI_FREE) != 0, vp, ("vnode not free"));
2873 VNASSERT(vp->v_op != NULL, vp, ("vbusy: vnode already reclaimed."));
2875 mtx_lock(&vnode_free_list_mtx);
2876 TAILQ_REMOVE(&vnode_free_list, vp, v_freelist);
2878 vp->v_iflag &= ~(VI_FREE|VI_AGE);
2879 mtx_unlock(&vnode_free_list_mtx);
2883 * Initalize per-vnode helper structure to hold poll-related state.
2886 v_addpollinfo(struct vnode *vp)
2888 struct vpollinfo *vi;
2890 vi = uma_zalloc(vnodepoll_zone, M_WAITOK);
2891 if (vp->v_pollinfo != NULL) {
2892 uma_zfree(vnodepoll_zone, vi);
2895 vp->v_pollinfo = vi;
2896 mtx_init(&vp->v_pollinfo->vpi_lock, "vnode pollinfo", NULL, MTX_DEF);
2897 knlist_init(&vp->v_pollinfo->vpi_selinfo.si_note, vp, vfs_knllock,
2898 vfs_knlunlock, vfs_knllocked);
2902 * Record a process's interest in events which might happen to
2903 * a vnode. Because poll uses the historic select-style interface
2904 * internally, this routine serves as both the ``check for any
2905 * pending events'' and the ``record my interest in future events''
2906 * functions. (These are done together, while the lock is held,
2907 * to avoid race conditions.)
2910 vn_pollrecord(struct vnode *vp, struct thread *td, int events)
2913 if (vp->v_pollinfo == NULL)
2915 mtx_lock(&vp->v_pollinfo->vpi_lock);
2916 if (vp->v_pollinfo->vpi_revents & events) {
2918 * This leaves events we are not interested
2919 * in available for the other process which
2920 * which presumably had requested them
2921 * (otherwise they would never have been
2924 events &= vp->v_pollinfo->vpi_revents;
2925 vp->v_pollinfo->vpi_revents &= ~events;
2927 mtx_unlock(&vp->v_pollinfo->vpi_lock);
2930 vp->v_pollinfo->vpi_events |= events;
2931 selrecord(td, &vp->v_pollinfo->vpi_selinfo);
2932 mtx_unlock(&vp->v_pollinfo->vpi_lock);
2937 * Routine to create and manage a filesystem syncer vnode.
2939 #define sync_close ((int (*)(struct vop_close_args *))nullop)
2940 static int sync_fsync(struct vop_fsync_args *);
2941 static int sync_inactive(struct vop_inactive_args *);
2942 static int sync_reclaim(struct vop_reclaim_args *);
2944 static struct vop_vector sync_vnodeops = {
2945 .vop_bypass = VOP_EOPNOTSUPP,
2946 .vop_close = sync_close, /* close */
2947 .vop_fsync = sync_fsync, /* fsync */
2948 .vop_inactive = sync_inactive, /* inactive */
2949 .vop_reclaim = sync_reclaim, /* reclaim */
2950 .vop_lock = vop_stdlock, /* lock */
2951 .vop_unlock = vop_stdunlock, /* unlock */
2952 .vop_islocked = vop_stdislocked, /* islocked */
2956 * Create a new filesystem syncer vnode for the specified mount point.
2959 vfs_allocate_syncvnode(struct mount *mp)
2962 static long start, incr, next;
2965 /* Allocate a new vnode */
2966 if ((error = getnewvnode("syncer", mp, &sync_vnodeops, &vp)) != 0) {
2967 mp->mnt_syncer = NULL;
2972 * Place the vnode onto the syncer worklist. We attempt to
2973 * scatter them about on the list so that they will go off
2974 * at evenly distributed times even if all the filesystems
2975 * are mounted at once.
2978 if (next == 0 || next > syncer_maxdelay) {
2982 start = syncer_maxdelay / 2;
2983 incr = syncer_maxdelay;
2988 vn_syncer_add_to_worklist(&vp->v_bufobj,
2989 syncdelay > 0 ? next % syncdelay : 0);
2990 /* XXX - vn_syncer_add_to_worklist() also grabs and drops sync_mtx. */
2991 mtx_lock(&sync_mtx);
2993 mtx_unlock(&sync_mtx);
2995 mp->mnt_syncer = vp;
3000 * Do a lazy sync of the filesystem.
3003 sync_fsync(struct vop_fsync_args *ap)
3005 struct vnode *syncvp = ap->a_vp;
3006 struct mount *mp = syncvp->v_mount;
3007 struct thread *td = ap->a_td;
3008 int error, asyncflag;
3012 * We only need to do something if this is a lazy evaluation.
3014 if (ap->a_waitfor != MNT_LAZY)
3018 * Move ourselves to the back of the sync list.
3020 bo = &syncvp->v_bufobj;
3022 vn_syncer_add_to_worklist(bo, syncdelay);
3026 * Walk the list of vnodes pushing all that are dirty and
3027 * not already on the sync list.
3029 mtx_lock(&mountlist_mtx);
3030 if (vfs_busy(mp, LK_EXCLUSIVE | LK_NOWAIT, &mountlist_mtx, td) != 0) {
3031 mtx_unlock(&mountlist_mtx);
3034 if (vn_start_write(NULL, &mp, V_NOWAIT) != 0) {
3038 asyncflag = mp->mnt_flag & MNT_ASYNC;
3039 mp->mnt_flag &= ~MNT_ASYNC;
3040 vfs_msync(mp, MNT_NOWAIT);
3041 error = VFS_SYNC(mp, MNT_LAZY, td);
3043 mp->mnt_flag |= MNT_ASYNC;
3044 vn_finished_write(mp);
3050 * The syncer vnode is no referenced.
3053 sync_inactive(struct vop_inactive_args *ap)
3061 * The syncer vnode is no longer needed and is being decommissioned.
3063 * Modifications to the worklist must be protected by sync_mtx.
3066 sync_reclaim(struct vop_reclaim_args *ap)
3068 struct vnode *vp = ap->a_vp;
3073 vp->v_mount->mnt_syncer = NULL;
3074 if (bo->bo_flag & BO_ONWORKLST) {
3075 mtx_lock(&sync_mtx);
3076 LIST_REMOVE(bo, bo_synclist);
3077 syncer_worklist_len--;
3079 mtx_unlock(&sync_mtx);
3080 bo->bo_flag &= ~BO_ONWORKLST;
3088 * Check if vnode represents a disk device
3091 vn_isdisk(struct vnode *vp, int *errp)
3097 if (vp->v_type != VCHR)
3099 else if (vp->v_rdev == NULL)
3101 else if (vp->v_rdev->si_devsw == NULL)
3103 else if (!(vp->v_rdev->si_devsw->d_flags & D_DISK))
3108 return (error == 0);
3112 * Common filesystem object access control check routine. Accepts a
3113 * vnode's type, "mode", uid and gid, requested access mode, credentials,
3114 * and optional call-by-reference privused argument allowing vaccess()
3115 * to indicate to the caller whether privilege was used to satisfy the
3116 * request (obsoleted). Returns 0 on success, or an errno on failure.
3119 vaccess(enum vtype type, mode_t file_mode, uid_t file_uid, gid_t file_gid,
3120 mode_t acc_mode, struct ucred *cred, int *privused)
3128 * Look for a normal, non-privileged way to access the file/directory
3129 * as requested. If it exists, go with that.
3132 if (privused != NULL)
3137 /* Check the owner. */
3138 if (cred->cr_uid == file_uid) {
3139 dac_granted |= VADMIN;
3140 if (file_mode & S_IXUSR)
3141 dac_granted |= VEXEC;
3142 if (file_mode & S_IRUSR)
3143 dac_granted |= VREAD;
3144 if (file_mode & S_IWUSR)
3145 dac_granted |= (VWRITE | VAPPEND);
3147 if ((acc_mode & dac_granted) == acc_mode)
3153 /* Otherwise, check the groups (first match) */
3154 if (groupmember(file_gid, cred)) {
3155 if (file_mode & S_IXGRP)
3156 dac_granted |= VEXEC;
3157 if (file_mode & S_IRGRP)
3158 dac_granted |= VREAD;
3159 if (file_mode & S_IWGRP)
3160 dac_granted |= (VWRITE | VAPPEND);
3162 if ((acc_mode & dac_granted) == acc_mode)
3168 /* Otherwise, check everyone else. */
3169 if (file_mode & S_IXOTH)
3170 dac_granted |= VEXEC;
3171 if (file_mode & S_IROTH)
3172 dac_granted |= VREAD;
3173 if (file_mode & S_IWOTH)
3174 dac_granted |= (VWRITE | VAPPEND);
3175 if ((acc_mode & dac_granted) == acc_mode)
3179 if (!suser_cred(cred, SUSER_ALLOWJAIL)) {
3180 /* XXX audit: privilege used */
3181 if (privused != NULL)
3188 * Build a capability mask to determine if the set of capabilities
3189 * satisfies the requirements when combined with the granted mask
3191 * For each capability, if the capability is required, bitwise
3192 * or the request type onto the cap_granted mask.
3198 * For directories, use CAP_DAC_READ_SEARCH to satisfy
3199 * VEXEC requests, instead of CAP_DAC_EXECUTE.
3201 if ((acc_mode & VEXEC) && ((dac_granted & VEXEC) == 0) &&
3202 !cap_check(cred, NULL, CAP_DAC_READ_SEARCH, SUSER_ALLOWJAIL))
3203 cap_granted |= VEXEC;
3205 if ((acc_mode & VEXEC) && ((dac_granted & VEXEC) == 0) &&
3206 !cap_check(cred, NULL, CAP_DAC_EXECUTE, SUSER_ALLOWJAIL))
3207 cap_granted |= VEXEC;
3210 if ((acc_mode & VREAD) && ((dac_granted & VREAD) == 0) &&
3211 !cap_check(cred, NULL, CAP_DAC_READ_SEARCH, SUSER_ALLOWJAIL))
3212 cap_granted |= VREAD;
3214 if ((acc_mode & VWRITE) && ((dac_granted & VWRITE) == 0) &&
3215 !cap_check(cred, NULL, CAP_DAC_WRITE, SUSER_ALLOWJAIL))
3216 cap_granted |= (VWRITE | VAPPEND);
3218 if ((acc_mode & VADMIN) && ((dac_granted & VADMIN) == 0) &&
3219 !cap_check(cred, NULL, CAP_FOWNER, SUSER_ALLOWJAIL))
3220 cap_granted |= VADMIN;
3222 if ((acc_mode & (cap_granted | dac_granted)) == acc_mode) {
3223 /* XXX audit: privilege used */
3224 if (privused != NULL)
3230 return ((acc_mode & VADMIN) ? EPERM : EACCES);
3234 * Credential check based on process requesting service, and per-attribute
3238 extattr_check_cred(struct vnode *vp, int attrnamespace, struct ucred *cred,
3239 struct thread *td, int access)
3243 * Kernel-invoked always succeeds.
3249 * Do not allow privileged processes in jail to directly
3250 * manipulate system attributes.
3252 * XXX What capability should apply here?
3253 * Probably CAP_SYS_SETFFLAG.
3255 switch (attrnamespace) {
3256 case EXTATTR_NAMESPACE_SYSTEM:
3257 /* Potentially should be: return (EPERM); */
3258 return (suser_cred(cred, 0));
3259 case EXTATTR_NAMESPACE_USER:
3260 return (VOP_ACCESS(vp, access, cred, td));
3266 #ifdef DEBUG_VFS_LOCKS
3268 * This only exists to supress warnings from unlocked specfs accesses. It is
3269 * no longer ok to have an unlocked VFS.
3271 #define IGNORE_LOCK(vp) ((vp)->v_type == VCHR || (vp)->v_type == VBAD)
3273 int vfs_badlock_ddb = 1; /* Drop into debugger on violation. */
3274 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_ddb, CTLFLAG_RW, &vfs_badlock_ddb, 0, "");
3276 int vfs_badlock_mutex = 1; /* Check for interlock across VOPs. */
3277 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_mutex, CTLFLAG_RW, &vfs_badlock_mutex, 0, "");
3279 int vfs_badlock_print = 1; /* Print lock violations. */
3280 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_print, CTLFLAG_RW, &vfs_badlock_print, 0, "");
3283 int vfs_badlock_backtrace = 1; /* Print backtrace at lock violations. */
3284 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_backtrace, CTLFLAG_RW, &vfs_badlock_backtrace, 0, "");
3288 vfs_badlock(const char *msg, const char *str, struct vnode *vp)
3292 if (vfs_badlock_backtrace)
3295 if (vfs_badlock_print)
3296 printf("%s: %p %s\n", str, (void *)vp, msg);
3297 if (vfs_badlock_ddb)
3298 kdb_enter("lock violation");
3302 assert_vi_locked(struct vnode *vp, const char *str)
3305 if (vfs_badlock_mutex && !mtx_owned(VI_MTX(vp)))
3306 vfs_badlock("interlock is not locked but should be", str, vp);
3310 assert_vi_unlocked(struct vnode *vp, const char *str)
3313 if (vfs_badlock_mutex && mtx_owned(VI_MTX(vp)))
3314 vfs_badlock("interlock is locked but should not be", str, vp);
3318 assert_vop_locked(struct vnode *vp, const char *str)
3321 if (vp && !IGNORE_LOCK(vp) && VOP_ISLOCKED(vp, NULL) == 0)
3322 vfs_badlock("is not locked but should be", str, vp);
3326 assert_vop_unlocked(struct vnode *vp, const char *str)
3329 if (vp && !IGNORE_LOCK(vp) &&
3330 VOP_ISLOCKED(vp, curthread) == LK_EXCLUSIVE)
3331 vfs_badlock("is locked but should not be", str, vp);
3335 assert_vop_elocked(struct vnode *vp, const char *str)
3338 if (vp && !IGNORE_LOCK(vp) &&
3339 VOP_ISLOCKED(vp, curthread) != LK_EXCLUSIVE)
3340 vfs_badlock("is not exclusive locked but should be", str, vp);
3345 assert_vop_elocked_other(struct vnode *vp, const char *str)
3348 if (vp && !IGNORE_LOCK(vp) &&
3349 VOP_ISLOCKED(vp, curthread) != LK_EXCLOTHER)
3350 vfs_badlock("is not exclusive locked by another thread",
3355 assert_vop_slocked(struct vnode *vp, const char *str)
3358 if (vp && !IGNORE_LOCK(vp) &&
3359 VOP_ISLOCKED(vp, curthread) != LK_SHARED)
3360 vfs_badlock("is not locked shared but should be", str, vp);
3363 #endif /* DEBUG_VFS_LOCKS */
3366 vop_rename_pre(void *ap)
3368 struct vop_rename_args *a = ap;
3370 #ifdef DEBUG_VFS_LOCKS
3372 ASSERT_VI_UNLOCKED(a->a_tvp, "VOP_RENAME");
3373 ASSERT_VI_UNLOCKED(a->a_tdvp, "VOP_RENAME");
3374 ASSERT_VI_UNLOCKED(a->a_fvp, "VOP_RENAME");
3375 ASSERT_VI_UNLOCKED(a->a_fdvp, "VOP_RENAME");
3377 /* Check the source (from). */
3378 if (a->a_tdvp != a->a_fdvp)
3379 ASSERT_VOP_UNLOCKED(a->a_fdvp, "vop_rename: fdvp locked");
3380 if (a->a_tvp != a->a_fvp)
3381 ASSERT_VOP_UNLOCKED(a->a_fvp, "vop_rename: tvp locked");
3383 /* Check the target. */
3385 ASSERT_VOP_LOCKED(a->a_tvp, "vop_rename: tvp not locked");
3386 ASSERT_VOP_LOCKED(a->a_tdvp, "vop_rename: tdvp not locked");
3388 if (a->a_tdvp != a->a_fdvp)
3390 if (a->a_tvp != a->a_fvp)
3398 vop_strategy_pre(void *ap)
3400 #ifdef DEBUG_VFS_LOCKS
3401 struct vop_strategy_args *a;
3408 * Cluster ops lock their component buffers but not the IO container.
3410 if ((bp->b_flags & B_CLUSTER) != 0)
3413 if (BUF_REFCNT(bp) < 1) {
3414 if (vfs_badlock_print)
3416 "VOP_STRATEGY: bp is not locked but should be\n");
3417 if (vfs_badlock_ddb)
3418 kdb_enter("lock violation");
3424 vop_lookup_pre(void *ap)
3426 #ifdef DEBUG_VFS_LOCKS
3427 struct vop_lookup_args *a;
3432 ASSERT_VI_UNLOCKED(dvp, "VOP_LOOKUP");
3433 ASSERT_VOP_LOCKED(dvp, "VOP_LOOKUP");
3438 vop_lookup_post(void *ap, int rc)
3440 #ifdef DEBUG_VFS_LOCKS
3441 struct vop_lookup_args *a;
3449 ASSERT_VI_UNLOCKED(dvp, "VOP_LOOKUP");
3450 ASSERT_VOP_LOCKED(dvp, "VOP_LOOKUP");
3453 ASSERT_VOP_LOCKED(vp, "VOP_LOOKUP (child)");
3458 vop_lock_pre(void *ap)
3460 #ifdef DEBUG_VFS_LOCKS
3461 struct vop_lock_args *a = ap;
3463 if ((a->a_flags & LK_INTERLOCK) == 0)
3464 ASSERT_VI_UNLOCKED(a->a_vp, "VOP_LOCK");
3466 ASSERT_VI_LOCKED(a->a_vp, "VOP_LOCK");
3471 vop_lock_post(void *ap, int rc)
3473 #ifdef DEBUG_VFS_LOCKS
3474 struct vop_lock_args *a = ap;
3476 ASSERT_VI_UNLOCKED(a->a_vp, "VOP_LOCK");
3478 ASSERT_VOP_LOCKED(a->a_vp, "VOP_LOCK");
3483 vop_unlock_pre(void *ap)
3485 #ifdef DEBUG_VFS_LOCKS
3486 struct vop_unlock_args *a = ap;
3488 if (a->a_flags & LK_INTERLOCK)
3489 ASSERT_VI_LOCKED(a->a_vp, "VOP_UNLOCK");
3490 ASSERT_VOP_LOCKED(a->a_vp, "VOP_UNLOCK");
3495 vop_unlock_post(void *ap, int rc)
3497 #ifdef DEBUG_VFS_LOCKS
3498 struct vop_unlock_args *a = ap;
3500 if (a->a_flags & LK_INTERLOCK)
3501 ASSERT_VI_UNLOCKED(a->a_vp, "VOP_UNLOCK");
3506 vop_create_post(void *ap, int rc)
3508 struct vop_create_args *a = ap;
3511 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE);
3515 vop_link_post(void *ap, int rc)
3517 struct vop_link_args *a = ap;
3520 VFS_KNOTE_LOCKED(a->a_vp, NOTE_LINK);
3521 VFS_KNOTE_LOCKED(a->a_tdvp, NOTE_WRITE);
3526 vop_mkdir_post(void *ap, int rc)
3528 struct vop_mkdir_args *a = ap;
3531 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE | NOTE_LINK);
3535 vop_mknod_post(void *ap, int rc)
3537 struct vop_mknod_args *a = ap;
3540 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE);
3544 vop_remove_post(void *ap, int rc)
3546 struct vop_remove_args *a = ap;
3549 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE);
3550 VFS_KNOTE_LOCKED(a->a_vp, NOTE_DELETE);
3555 vop_rename_post(void *ap, int rc)
3557 struct vop_rename_args *a = ap;
3560 VFS_KNOTE_UNLOCKED(a->a_fdvp, NOTE_WRITE);
3561 VFS_KNOTE_UNLOCKED(a->a_tdvp, NOTE_WRITE);
3562 VFS_KNOTE_UNLOCKED(a->a_fvp, NOTE_RENAME);
3564 VFS_KNOTE_UNLOCKED(a->a_tvp, NOTE_DELETE);
3566 if (a->a_tdvp != a->a_fdvp)
3568 if (a->a_tvp != a->a_fvp)
3576 vop_rmdir_post(void *ap, int rc)
3578 struct vop_rmdir_args *a = ap;
3581 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE | NOTE_LINK);
3582 VFS_KNOTE_LOCKED(a->a_vp, NOTE_DELETE);
3587 vop_setattr_post(void *ap, int rc)
3589 struct vop_setattr_args *a = ap;
3592 VFS_KNOTE_LOCKED(a->a_vp, NOTE_ATTRIB);
3596 vop_symlink_post(void *ap, int rc)
3598 struct vop_symlink_args *a = ap;
3601 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE);
3604 static struct knlist fs_knlist;
3607 vfs_event_init(void *arg)
3609 knlist_init(&fs_knlist, NULL, NULL, NULL, NULL);
3611 /* XXX - correct order? */
3612 SYSINIT(vfs_knlist, SI_SUB_VFS, SI_ORDER_ANY, vfs_event_init, NULL);
3615 vfs_event_signal(fsid_t *fsid, u_int32_t event, intptr_t data __unused)
3618 KNOTE_UNLOCKED(&fs_knlist, event);
3621 static int filt_fsattach(struct knote *kn);
3622 static void filt_fsdetach(struct knote *kn);
3623 static int filt_fsevent(struct knote *kn, long hint);
3625 struct filterops fs_filtops =
3626 { 0, filt_fsattach, filt_fsdetach, filt_fsevent };
3629 filt_fsattach(struct knote *kn)
3632 kn->kn_flags |= EV_CLEAR;
3633 knlist_add(&fs_knlist, kn, 0);
3638 filt_fsdetach(struct knote *kn)
3641 knlist_remove(&fs_knlist, kn, 0);
3645 filt_fsevent(struct knote *kn, long hint)
3648 kn->kn_fflags |= hint;
3649 return (kn->kn_fflags != 0);
3653 sysctl_vfs_ctl(SYSCTL_HANDLER_ARGS)
3659 error = SYSCTL_IN(req, &vc, sizeof(vc));
3662 if (vc.vc_vers != VFS_CTL_VERS1)
3664 mp = vfs_getvfs(&vc.vc_fsid);
3667 /* ensure that a specific sysctl goes to the right filesystem. */
3668 if (strcmp(vc.vc_fstypename, "*") != 0 &&
3669 strcmp(vc.vc_fstypename, mp->mnt_vfc->vfc_name) != 0) {
3672 VCTLTOREQ(&vc, req);
3673 return (VFS_SYSCTL(mp, vc.vc_op, req));
3676 SYSCTL_PROC(_vfs, OID_AUTO, ctl, CTLFLAG_WR,
3677 NULL, 0, sysctl_vfs_ctl, "", "Sysctl by fsid");
3680 * Function to initialize a va_filerev field sensibly.
3681 * XXX: Wouldn't a random number make a lot more sense ??
3684 init_va_filerev(void)
3689 return (((u_quad_t)bt.sec << 32LL) | (bt.frac >> 32LL));
3692 static int filt_vfsread(struct knote *kn, long hint);
3693 static int filt_vfswrite(struct knote *kn, long hint);
3694 static int filt_vfsvnode(struct knote *kn, long hint);
3695 static void filt_vfsdetach(struct knote *kn);
3696 static struct filterops vfsread_filtops =
3697 { 1, NULL, filt_vfsdetach, filt_vfsread };
3698 static struct filterops vfswrite_filtops =
3699 { 1, NULL, filt_vfsdetach, filt_vfswrite };
3700 static struct filterops vfsvnode_filtops =
3701 { 1, NULL, filt_vfsdetach, filt_vfsvnode };
3704 vfs_knllock(void *arg)
3706 struct vnode *vp = arg;
3708 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, curthread);
3712 vfs_knlunlock(void *arg)
3714 struct vnode *vp = arg;
3716 VOP_UNLOCK(vp, 0, curthread);
3720 vfs_knllocked(void *arg)
3722 struct vnode *vp = arg;
3724 return (VOP_ISLOCKED(vp, curthread) == LK_EXCLUSIVE);
3728 vfs_kqfilter(struct vop_kqfilter_args *ap)
3730 struct vnode *vp = ap->a_vp;
3731 struct knote *kn = ap->a_kn;
3734 switch (kn->kn_filter) {
3736 kn->kn_fop = &vfsread_filtops;
3739 kn->kn_fop = &vfswrite_filtops;
3742 kn->kn_fop = &vfsvnode_filtops;
3748 kn->kn_hook = (caddr_t)vp;
3750 if (vp->v_pollinfo == NULL)
3752 if (vp->v_pollinfo == NULL)
3754 knl = &vp->v_pollinfo->vpi_selinfo.si_note;
3755 knlist_add(knl, kn, 0);
3761 * Detach knote from vnode
3764 filt_vfsdetach(struct knote *kn)
3766 struct vnode *vp = (struct vnode *)kn->kn_hook;
3768 KASSERT(vp->v_pollinfo != NULL, ("Missing v_pollinfo"));
3769 knlist_remove(&vp->v_pollinfo->vpi_selinfo.si_note, kn, 0);
3774 filt_vfsread(struct knote *kn, long hint)
3776 struct vnode *vp = (struct vnode *)kn->kn_hook;
3780 * filesystem is gone, so set the EOF flag and schedule
3781 * the knote for deletion.
3783 if (hint == NOTE_REVOKE) {
3784 kn->kn_flags |= (EV_EOF | EV_ONESHOT);
3788 if (VOP_GETATTR(vp, &va, curthread->td_ucred, curthread))
3791 kn->kn_data = va.va_size - kn->kn_fp->f_offset;
3792 return (kn->kn_data != 0);
3797 filt_vfswrite(struct knote *kn, long hint)
3800 * filesystem is gone, so set the EOF flag and schedule
3801 * the knote for deletion.
3803 if (hint == NOTE_REVOKE)
3804 kn->kn_flags |= (EV_EOF | EV_ONESHOT);
3811 filt_vfsvnode(struct knote *kn, long hint)
3813 if (kn->kn_sfflags & hint)
3814 kn->kn_fflags |= hint;
3815 if (hint == NOTE_REVOKE) {
3816 kn->kn_flags |= EV_EOF;
3819 return (kn->kn_fflags != 0);
3823 vfs_read_dirent(struct vop_readdir_args *ap, struct dirent *dp, off_t off)
3827 if (dp->d_reclen > ap->a_uio->uio_resid)
3828 return (ENAMETOOLONG);
3829 error = uiomove(dp, dp->d_reclen, ap->a_uio);
3831 if (ap->a_ncookies != NULL) {
3832 if (ap->a_cookies != NULL)
3833 free(ap->a_cookies, M_TEMP);
3834 ap->a_cookies = NULL;
3835 *ap->a_ncookies = 0;
3839 if (ap->a_ncookies == NULL)
3842 KASSERT(ap->a_cookies,
3843 ("NULL ap->a_cookies value with non-NULL ap->a_ncookies!"));
3845 *ap->a_cookies = realloc(*ap->a_cookies,
3846 (*ap->a_ncookies + 1) * sizeof(u_long), M_TEMP, M_WAITOK | M_ZERO);
3847 (*ap->a_cookies)[*ap->a_ncookies] = off;
3852 * Mark for update the access time of the file if the filesystem
3853 * supports VA_MARK_ATIME. This functionality is used by execve
3854 * and mmap, so we want to avoid the synchronous I/O implied by
3855 * directly setting va_atime for the sake of efficiency.
3858 vfs_mark_atime(struct vnode *vp, struct thread *td)
3860 struct vattr atimeattr;
3862 if ((vp->v_mount->mnt_flag & (MNT_NOATIME | MNT_RDONLY)) == 0) {
3863 VATTR_NULL(&atimeattr);
3864 atimeattr.va_vaflags |= VA_MARK_ATIME;
3865 (void)VOP_SETATTR(vp, &atimeattr, td->td_ucred, td);