2 * SPDX-License-Identifier: BSD-3-Clause
4 * Copyright (c) 1989, 1993
5 * The Regents of the University of California. All rights reserved.
6 * (c) UNIX System Laboratories, Inc.
7 * All or some portions of this file are derived from material licensed
8 * to the University of California by American Telephone and Telegraph
9 * Co. or Unix System Laboratories, Inc. and are reproduced herein with
10 * the permission of UNIX System Laboratories, Inc.
12 * Redistribution and use in source and binary forms, with or without
13 * modification, are permitted provided that the following conditions
15 * 1. Redistributions of source code must retain the above copyright
16 * notice, this list of conditions and the following disclaimer.
17 * 2. Redistributions in binary form must reproduce the above copyright
18 * notice, this list of conditions and the following disclaimer in the
19 * documentation and/or other materials provided with the distribution.
20 * 3. Neither the name of the University nor the names of its contributors
21 * may be used to endorse or promote products derived from this software
22 * without specific prior written permission.
24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36 * @(#)vfs_subr.c 8.31 (Berkeley) 5/26/95
40 * External virtual filesystem routines
43 #include <sys/cdefs.h>
44 __FBSDID("$FreeBSD$");
47 #include "opt_watchdog.h"
49 #include <sys/param.h>
50 #include <sys/systm.h>
53 #include <sys/capsicum.h>
54 #include <sys/condvar.h>
56 #include <sys/counter.h>
57 #include <sys/dirent.h>
58 #include <sys/event.h>
59 #include <sys/eventhandler.h>
60 #include <sys/extattr.h>
62 #include <sys/fcntl.h>
65 #include <sys/kernel.h>
66 #include <sys/kthread.h>
68 #include <sys/lockf.h>
69 #include <sys/malloc.h>
70 #include <sys/mount.h>
71 #include <sys/namei.h>
72 #include <sys/pctrie.h>
74 #include <sys/reboot.h>
75 #include <sys/refcount.h>
76 #include <sys/rwlock.h>
77 #include <sys/sched.h>
78 #include <sys/sleepqueue.h>
82 #include <sys/sysctl.h>
83 #include <sys/syslog.h>
84 #include <sys/vmmeter.h>
85 #include <sys/vnode.h>
86 #include <sys/watchdog.h>
88 #include <machine/stdarg.h>
90 #include <security/mac/mac_framework.h>
93 #include <vm/vm_object.h>
94 #include <vm/vm_extern.h>
96 #include <vm/vm_map.h>
97 #include <vm/vm_page.h>
98 #include <vm/vm_kern.h>
105 static void delmntque(struct vnode *vp);
106 static int flushbuflist(struct bufv *bufv, int flags, struct bufobj *bo,
107 int slpflag, int slptimeo);
108 static void syncer_shutdown(void *arg, int howto);
109 static int vtryrecycle(struct vnode *vp);
110 static void v_init_counters(struct vnode *);
111 static void vgonel(struct vnode *);
112 static void vfs_knllock(void *arg);
113 static void vfs_knlunlock(void *arg);
114 static void vfs_knl_assert_locked(void *arg);
115 static void vfs_knl_assert_unlocked(void *arg);
116 static void destroy_vpollinfo(struct vpollinfo *vi);
117 static int v_inval_buf_range_locked(struct vnode *vp, struct bufobj *bo,
118 daddr_t startlbn, daddr_t endlbn);
119 static void vnlru_recalc(void);
122 * These fences are intended for cases where some synchronization is
123 * needed between access of v_iflags and lockless vnode refcount (v_holdcnt
124 * and v_usecount) updates. Access to v_iflags is generally synchronized
125 * by the interlock, but we have some internal assertions that check vnode
126 * flags without acquiring the lock. Thus, these fences are INVARIANTS-only
130 #define VNODE_REFCOUNT_FENCE_ACQ() atomic_thread_fence_acq()
131 #define VNODE_REFCOUNT_FENCE_REL() atomic_thread_fence_rel()
133 #define VNODE_REFCOUNT_FENCE_ACQ()
134 #define VNODE_REFCOUNT_FENCE_REL()
138 * Number of vnodes in existence. Increased whenever getnewvnode()
139 * allocates a new vnode, decreased in vdropl() for VIRF_DOOMED vnode.
141 static u_long __exclusive_cache_line numvnodes;
143 SYSCTL_ULONG(_vfs, OID_AUTO, numvnodes, CTLFLAG_RD, &numvnodes, 0,
144 "Number of vnodes in existence");
146 static counter_u64_t vnodes_created;
147 SYSCTL_COUNTER_U64(_vfs, OID_AUTO, vnodes_created, CTLFLAG_RD, &vnodes_created,
148 "Number of vnodes created by getnewvnode");
151 * Conversion tables for conversion from vnode types to inode formats
154 enum vtype iftovt_tab[16] = {
155 VNON, VFIFO, VCHR, VNON, VDIR, VNON, VBLK, VNON,
156 VREG, VNON, VLNK, VNON, VSOCK, VNON, VNON, VNON
158 int vttoif_tab[10] = {
159 0, S_IFREG, S_IFDIR, S_IFBLK, S_IFCHR, S_IFLNK,
160 S_IFSOCK, S_IFIFO, S_IFMT, S_IFMT
164 * List of allocates vnodes in the system.
166 static TAILQ_HEAD(freelst, vnode) vnode_list;
167 static struct vnode *vnode_list_free_marker;
168 static struct vnode *vnode_list_reclaim_marker;
171 * "Free" vnode target. Free vnodes are rarely completely free, but are
172 * just ones that are cheap to recycle. Usually they are for files which
173 * have been stat'd but not read; these usually have inode and namecache
174 * data attached to them. This target is the preferred minimum size of a
175 * sub-cache consisting mostly of such files. The system balances the size
176 * of this sub-cache with its complement to try to prevent either from
177 * thrashing while the other is relatively inactive. The targets express
178 * a preference for the best balance.
180 * "Above" this target there are 2 further targets (watermarks) related
181 * to recyling of free vnodes. In the best-operating case, the cache is
182 * exactly full, the free list has size between vlowat and vhiwat above the
183 * free target, and recycling from it and normal use maintains this state.
184 * Sometimes the free list is below vlowat or even empty, but this state
185 * is even better for immediate use provided the cache is not full.
186 * Otherwise, vnlru_proc() runs to reclaim enough vnodes (usually non-free
187 * ones) to reach one of these states. The watermarks are currently hard-
188 * coded as 4% and 9% of the available space higher. These and the default
189 * of 25% for wantfreevnodes are too large if the memory size is large.
190 * E.g., 9% of 75% of MAXVNODES is more than 566000 vnodes to reclaim
191 * whenever vnlru_proc() becomes active.
193 static long wantfreevnodes;
194 static long __exclusive_cache_line freevnodes;
195 SYSCTL_ULONG(_vfs, OID_AUTO, freevnodes, CTLFLAG_RD,
196 &freevnodes, 0, "Number of \"free\" vnodes");
197 static long freevnodes_old;
199 static counter_u64_t recycles_count;
200 SYSCTL_COUNTER_U64(_vfs, OID_AUTO, recycles, CTLFLAG_RD, &recycles_count,
201 "Number of vnodes recycled to meet vnode cache targets");
203 static counter_u64_t recycles_free_count;
204 SYSCTL_COUNTER_U64(_vfs, OID_AUTO, recycles_free, CTLFLAG_RD, &recycles_free_count,
205 "Number of free vnodes recycled to meet vnode cache targets");
207 static counter_u64_t deferred_inact;
208 SYSCTL_COUNTER_U64(_vfs, OID_AUTO, deferred_inact, CTLFLAG_RD, &deferred_inact,
209 "Number of times inactive processing was deferred");
211 /* To keep more than one thread at a time from running vfs_getnewfsid */
212 static struct mtx mntid_mtx;
215 * Lock for any access to the following:
220 static struct mtx __exclusive_cache_line vnode_list_mtx;
222 /* Publicly exported FS */
223 struct nfs_public nfs_pub;
225 static uma_zone_t buf_trie_zone;
226 static smr_t buf_trie_smr;
228 /* Zone for allocation of new vnodes - used exclusively by getnewvnode() */
229 static uma_zone_t vnode_zone;
230 static uma_zone_t vnodepoll_zone;
232 __read_frequently smr_t vfs_smr;
235 * The workitem queue.
237 * It is useful to delay writes of file data and filesystem metadata
238 * for tens of seconds so that quickly created and deleted files need
239 * not waste disk bandwidth being created and removed. To realize this,
240 * we append vnodes to a "workitem" queue. When running with a soft
241 * updates implementation, most pending metadata dependencies should
242 * not wait for more than a few seconds. Thus, mounted on block devices
243 * are delayed only about a half the time that file data is delayed.
244 * Similarly, directory updates are more critical, so are only delayed
245 * about a third the time that file data is delayed. Thus, there are
246 * SYNCER_MAXDELAY queues that are processed round-robin at a rate of
247 * one each second (driven off the filesystem syncer process). The
248 * syncer_delayno variable indicates the next queue that is to be processed.
249 * Items that need to be processed soon are placed in this queue:
251 * syncer_workitem_pending[syncer_delayno]
253 * A delay of fifteen seconds is done by placing the request fifteen
254 * entries later in the queue:
256 * syncer_workitem_pending[(syncer_delayno + 15) & syncer_mask]
259 static int syncer_delayno;
260 static long syncer_mask;
261 LIST_HEAD(synclist, bufobj);
262 static struct synclist *syncer_workitem_pending;
264 * The sync_mtx protects:
269 * syncer_workitem_pending
270 * syncer_worklist_len
273 static struct mtx sync_mtx;
274 static struct cv sync_wakeup;
276 #define SYNCER_MAXDELAY 32
277 static int syncer_maxdelay = SYNCER_MAXDELAY; /* maximum delay time */
278 static int syncdelay = 30; /* max time to delay syncing data */
279 static int filedelay = 30; /* time to delay syncing files */
280 SYSCTL_INT(_kern, OID_AUTO, filedelay, CTLFLAG_RW, &filedelay, 0,
281 "Time to delay syncing files (in seconds)");
282 static int dirdelay = 29; /* time to delay syncing directories */
283 SYSCTL_INT(_kern, OID_AUTO, dirdelay, CTLFLAG_RW, &dirdelay, 0,
284 "Time to delay syncing directories (in seconds)");
285 static int metadelay = 28; /* time to delay syncing metadata */
286 SYSCTL_INT(_kern, OID_AUTO, metadelay, CTLFLAG_RW, &metadelay, 0,
287 "Time to delay syncing metadata (in seconds)");
288 static int rushjob; /* number of slots to run ASAP */
289 static int stat_rush_requests; /* number of times I/O speeded up */
290 SYSCTL_INT(_debug, OID_AUTO, rush_requests, CTLFLAG_RW, &stat_rush_requests, 0,
291 "Number of times I/O speeded up (rush requests)");
293 #define VDBATCH_SIZE 8
298 struct vnode *tab[VDBATCH_SIZE];
300 DPCPU_DEFINE_STATIC(struct vdbatch, vd);
302 static void vdbatch_dequeue(struct vnode *vp);
305 * When shutting down the syncer, run it at four times normal speed.
307 #define SYNCER_SHUTDOWN_SPEEDUP 4
308 static int sync_vnode_count;
309 static int syncer_worklist_len;
310 static enum { SYNCER_RUNNING, SYNCER_SHUTTING_DOWN, SYNCER_FINAL_DELAY }
313 /* Target for maximum number of vnodes. */
314 u_long desiredvnodes;
315 static u_long gapvnodes; /* gap between wanted and desired */
316 static u_long vhiwat; /* enough extras after expansion */
317 static u_long vlowat; /* minimal extras before expansion */
318 static u_long vstir; /* nonzero to stir non-free vnodes */
319 static volatile int vsmalltrigger = 8; /* pref to keep if > this many pages */
321 static u_long vnlru_read_freevnodes(void);
324 * Note that no attempt is made to sanitize these parameters.
327 sysctl_maxvnodes(SYSCTL_HANDLER_ARGS)
333 error = sysctl_handle_long(oidp, &val, 0, req);
334 if (error != 0 || req->newptr == NULL)
337 if (val == desiredvnodes)
339 mtx_lock(&vnode_list_mtx);
341 wantfreevnodes = desiredvnodes / 4;
343 mtx_unlock(&vnode_list_mtx);
345 * XXX There is no protection against multiple threads changing
346 * desiredvnodes at the same time. Locking above only helps vnlru and
349 vfs_hash_changesize(desiredvnodes);
350 cache_changesize(desiredvnodes);
354 SYSCTL_PROC(_kern, KERN_MAXVNODES, maxvnodes,
355 CTLTYPE_ULONG | CTLFLAG_MPSAFE | CTLFLAG_RW, NULL, 0, sysctl_maxvnodes,
356 "LU", "Target for maximum number of vnodes");
359 sysctl_wantfreevnodes(SYSCTL_HANDLER_ARGS)
364 val = wantfreevnodes;
365 error = sysctl_handle_long(oidp, &val, 0, req);
366 if (error != 0 || req->newptr == NULL)
369 if (val == wantfreevnodes)
371 mtx_lock(&vnode_list_mtx);
372 wantfreevnodes = val;
374 mtx_unlock(&vnode_list_mtx);
378 SYSCTL_PROC(_vfs, OID_AUTO, wantfreevnodes,
379 CTLTYPE_ULONG | CTLFLAG_MPSAFE | CTLFLAG_RW, NULL, 0, sysctl_wantfreevnodes,
380 "LU", "Target for minimum number of \"free\" vnodes");
382 SYSCTL_ULONG(_kern, OID_AUTO, minvnodes, CTLFLAG_RW,
383 &wantfreevnodes, 0, "Old name for vfs.wantfreevnodes (legacy)");
384 static int vnlru_nowhere;
385 SYSCTL_INT(_debug, OID_AUTO, vnlru_nowhere, CTLFLAG_RW,
386 &vnlru_nowhere, 0, "Number of times the vnlru process ran without success");
389 sysctl_try_reclaim_vnode(SYSCTL_HANDLER_ARGS)
394 unsigned long ndflags;
397 if (req->newptr == NULL)
399 if (req->newlen >= PATH_MAX)
402 buf = malloc(PATH_MAX, M_TEMP, M_WAITOK);
403 error = SYSCTL_IN(req, buf, req->newlen);
407 buf[req->newlen] = '\0';
409 ndflags = LOCKLEAF | NOFOLLOW | AUDITVNODE1 | SAVENAME;
410 NDINIT(&nd, LOOKUP, ndflags, UIO_SYSSPACE, buf, curthread);
411 if ((error = namei(&nd)) != 0)
415 if (VN_IS_DOOMED(vp)) {
417 * This vnode is being recycled. Return != 0 to let the caller
418 * know that the sysctl had no effect. Return EAGAIN because a
419 * subsequent call will likely succeed (since namei will create
420 * a new vnode if necessary)
426 counter_u64_add(recycles_count, 1);
436 sysctl_ftry_reclaim_vnode(SYSCTL_HANDLER_ARGS)
438 struct thread *td = curthread;
444 if (req->newptr == NULL)
447 error = sysctl_handle_int(oidp, &fd, 0, req);
450 error = getvnode(curthread, fd, &cap_fcntl_rights, &fp);
455 error = vn_lock(vp, LK_EXCLUSIVE);
459 counter_u64_add(recycles_count, 1);
467 SYSCTL_PROC(_debug, OID_AUTO, try_reclaim_vnode,
468 CTLTYPE_STRING | CTLFLAG_MPSAFE | CTLFLAG_WR, NULL, 0,
469 sysctl_try_reclaim_vnode, "A", "Try to reclaim a vnode by its pathname");
470 SYSCTL_PROC(_debug, OID_AUTO, ftry_reclaim_vnode,
471 CTLTYPE_INT | CTLFLAG_MPSAFE | CTLFLAG_WR, NULL, 0,
472 sysctl_ftry_reclaim_vnode, "I",
473 "Try to reclaim a vnode by its file descriptor");
475 /* Shift count for (uintptr_t)vp to initialize vp->v_hash. */
479 * Support for the bufobj clean & dirty pctrie.
482 buf_trie_alloc(struct pctrie *ptree)
484 return (uma_zalloc_smr(buf_trie_zone, M_NOWAIT));
488 buf_trie_free(struct pctrie *ptree, void *node)
490 uma_zfree_smr(buf_trie_zone, node);
492 PCTRIE_DEFINE_SMR(BUF, buf, b_lblkno, buf_trie_alloc, buf_trie_free,
496 * Initialize the vnode management data structures.
498 * Reevaluate the following cap on the number of vnodes after the physical
499 * memory size exceeds 512GB. In the limit, as the physical memory size
500 * grows, the ratio of the memory size in KB to vnodes approaches 64:1.
502 #ifndef MAXVNODES_MAX
503 #define MAXVNODES_MAX (512UL * 1024 * 1024 / 64) /* 8M */
506 static MALLOC_DEFINE(M_VNODE_MARKER, "vnodemarker", "vnode marker");
508 static struct vnode *
509 vn_alloc_marker(struct mount *mp)
513 vp = malloc(sizeof(struct vnode), M_VNODE_MARKER, M_WAITOK | M_ZERO);
514 vp->v_type = VMARKER;
521 vn_free_marker(struct vnode *vp)
524 MPASS(vp->v_type == VMARKER);
525 free(vp, M_VNODE_MARKER);
529 * Initialize a vnode as it first enters the zone.
532 vnode_init(void *mem, int size, int flags)
541 vp->v_vnlock = &vp->v_lock;
542 mtx_init(&vp->v_interlock, "vnode interlock", NULL, MTX_DEF);
544 * By default, don't allow shared locks unless filesystems opt-in.
546 lockinit(vp->v_vnlock, PVFS, "vnode", VLKTIMEOUT,
547 LK_NOSHARE | LK_IS_VNODE);
551 bufobj_init(&vp->v_bufobj, vp);
553 * Initialize namecache.
555 cache_vnode_init(vp);
557 * Initialize rangelocks.
559 rangelock_init(&vp->v_rl);
561 vp->v_dbatchcpu = NOCPU;
563 mtx_lock(&vnode_list_mtx);
564 TAILQ_INSERT_BEFORE(vnode_list_free_marker, vp, v_vnodelist);
565 mtx_unlock(&vnode_list_mtx);
570 * Free a vnode when it is cleared from the zone.
573 vnode_fini(void *mem, int size)
580 mtx_lock(&vnode_list_mtx);
581 TAILQ_REMOVE(&vnode_list, vp, v_vnodelist);
582 mtx_unlock(&vnode_list_mtx);
583 rangelock_destroy(&vp->v_rl);
584 lockdestroy(vp->v_vnlock);
585 mtx_destroy(&vp->v_interlock);
587 rw_destroy(BO_LOCKPTR(bo));
591 * Provide the size of NFS nclnode and NFS fh for calculation of the
592 * vnode memory consumption. The size is specified directly to
593 * eliminate dependency on NFS-private header.
595 * Other filesystems may use bigger or smaller (like UFS and ZFS)
596 * private inode data, but the NFS-based estimation is ample enough.
597 * Still, we care about differences in the size between 64- and 32-bit
600 * Namecache structure size is heuristically
601 * sizeof(struct namecache_ts) + CACHE_PATH_CUTOFF + 1.
604 #define NFS_NCLNODE_SZ (528 + 64)
607 #define NFS_NCLNODE_SZ (360 + 32)
612 vntblinit(void *dummy __unused)
615 int cpu, physvnodes, virtvnodes;
619 * Desiredvnodes is a function of the physical memory size and the
620 * kernel's heap size. Generally speaking, it scales with the
621 * physical memory size. The ratio of desiredvnodes to the physical
622 * memory size is 1:16 until desiredvnodes exceeds 98,304.
624 * marginal ratio of desiredvnodes to the physical memory size is
625 * 1:64. However, desiredvnodes is limited by the kernel's heap
626 * size. The memory required by desiredvnodes vnodes and vm objects
627 * must not exceed 1/10th of the kernel's heap size.
629 physvnodes = maxproc + pgtok(vm_cnt.v_page_count) / 64 +
630 3 * min(98304 * 16, pgtok(vm_cnt.v_page_count)) / 64;
631 virtvnodes = vm_kmem_size / (10 * (sizeof(struct vm_object) +
632 sizeof(struct vnode) + NC_SZ * ncsizefactor + NFS_NCLNODE_SZ));
633 desiredvnodes = min(physvnodes, virtvnodes);
634 if (desiredvnodes > MAXVNODES_MAX) {
636 printf("Reducing kern.maxvnodes %lu -> %lu\n",
637 desiredvnodes, MAXVNODES_MAX);
638 desiredvnodes = MAXVNODES_MAX;
640 wantfreevnodes = desiredvnodes / 4;
641 mtx_init(&mntid_mtx, "mntid", NULL, MTX_DEF);
642 TAILQ_INIT(&vnode_list);
643 mtx_init(&vnode_list_mtx, "vnode_list", NULL, MTX_DEF);
645 * The lock is taken to appease WITNESS.
647 mtx_lock(&vnode_list_mtx);
649 mtx_unlock(&vnode_list_mtx);
650 vnode_list_free_marker = vn_alloc_marker(NULL);
651 TAILQ_INSERT_HEAD(&vnode_list, vnode_list_free_marker, v_vnodelist);
652 vnode_list_reclaim_marker = vn_alloc_marker(NULL);
653 TAILQ_INSERT_HEAD(&vnode_list, vnode_list_reclaim_marker, v_vnodelist);
654 vnode_zone = uma_zcreate("VNODE", sizeof (struct vnode), NULL, NULL,
655 vnode_init, vnode_fini, UMA_ALIGN_PTR, 0);
656 uma_zone_set_smr(vnode_zone, vfs_smr);
657 vnodepoll_zone = uma_zcreate("VNODEPOLL", sizeof (struct vpollinfo),
658 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0);
660 * Preallocate enough nodes to support one-per buf so that
661 * we can not fail an insert. reassignbuf() callers can not
662 * tolerate the insertion failure.
664 buf_trie_zone = uma_zcreate("BUF TRIE", pctrie_node_size(),
665 NULL, NULL, pctrie_zone_init, NULL, UMA_ALIGN_PTR,
666 UMA_ZONE_NOFREE | UMA_ZONE_SMR);
667 buf_trie_smr = uma_zone_get_smr(buf_trie_zone);
668 uma_prealloc(buf_trie_zone, nbuf);
670 vnodes_created = counter_u64_alloc(M_WAITOK);
671 recycles_count = counter_u64_alloc(M_WAITOK);
672 recycles_free_count = counter_u64_alloc(M_WAITOK);
673 deferred_inact = counter_u64_alloc(M_WAITOK);
676 * Initialize the filesystem syncer.
678 syncer_workitem_pending = hashinit(syncer_maxdelay, M_VNODE,
680 syncer_maxdelay = syncer_mask + 1;
681 mtx_init(&sync_mtx, "Syncer mtx", NULL, MTX_DEF);
682 cv_init(&sync_wakeup, "syncer");
683 for (i = 1; i <= sizeof(struct vnode); i <<= 1)
688 vd = DPCPU_ID_PTR((cpu), vd);
689 bzero(vd, sizeof(*vd));
690 mtx_init(&vd->lock, "vdbatch", NULL, MTX_DEF);
693 SYSINIT(vfs, SI_SUB_VFS, SI_ORDER_FIRST, vntblinit, NULL);
696 * Mark a mount point as busy. Used to synchronize access and to delay
697 * unmounting. Eventually, mountlist_mtx is not released on failure.
699 * vfs_busy() is a custom lock, it can block the caller.
700 * vfs_busy() only sleeps if the unmount is active on the mount point.
701 * For a mountpoint mp, vfs_busy-enforced lock is before lock of any
702 * vnode belonging to mp.
704 * Lookup uses vfs_busy() to traverse mount points.
706 * / vnode lock A / vnode lock (/var) D
707 * /var vnode lock B /log vnode lock(/var/log) E
708 * vfs_busy lock C vfs_busy lock F
710 * Within each file system, the lock order is C->A->B and F->D->E.
712 * When traversing across mounts, the system follows that lock order:
718 * The lookup() process for namei("/var") illustrates the process:
719 * VOP_LOOKUP() obtains B while A is held
720 * vfs_busy() obtains a shared lock on F while A and B are held
721 * vput() releases lock on B
722 * vput() releases lock on A
723 * VFS_ROOT() obtains lock on D while shared lock on F is held
724 * vfs_unbusy() releases shared lock on F
725 * vn_lock() obtains lock on deadfs vnode vp_crossmp instead of A.
726 * Attempt to lock A (instead of vp_crossmp) while D is held would
727 * violate the global order, causing deadlocks.
729 * dounmount() locks B while F is drained.
732 vfs_busy(struct mount *mp, int flags)
735 MPASS((flags & ~MBF_MASK) == 0);
736 CTR3(KTR_VFS, "%s: mp %p with flags %d", __func__, mp, flags);
738 if (vfs_op_thread_enter(mp)) {
739 MPASS((mp->mnt_kern_flag & MNTK_DRAINING) == 0);
740 MPASS((mp->mnt_kern_flag & MNTK_UNMOUNT) == 0);
741 MPASS((mp->mnt_kern_flag & MNTK_REFEXPIRE) == 0);
742 vfs_mp_count_add_pcpu(mp, ref, 1);
743 vfs_mp_count_add_pcpu(mp, lockref, 1);
744 vfs_op_thread_exit(mp);
745 if (flags & MBF_MNTLSTLOCK)
746 mtx_unlock(&mountlist_mtx);
751 vfs_assert_mount_counters(mp);
754 * If mount point is currently being unmounted, sleep until the
755 * mount point fate is decided. If thread doing the unmounting fails,
756 * it will clear MNTK_UNMOUNT flag before waking us up, indicating
757 * that this mount point has survived the unmount attempt and vfs_busy
758 * should retry. Otherwise the unmounter thread will set MNTK_REFEXPIRE
759 * flag in addition to MNTK_UNMOUNT, indicating that mount point is
760 * about to be really destroyed. vfs_busy needs to release its
761 * reference on the mount point in this case and return with ENOENT,
762 * telling the caller that mount mount it tried to busy is no longer
765 while (mp->mnt_kern_flag & MNTK_UNMOUNT) {
766 if (flags & MBF_NOWAIT || mp->mnt_kern_flag & MNTK_REFEXPIRE) {
769 CTR1(KTR_VFS, "%s: failed busying before sleeping",
773 if (flags & MBF_MNTLSTLOCK)
774 mtx_unlock(&mountlist_mtx);
775 mp->mnt_kern_flag |= MNTK_MWAIT;
776 msleep(mp, MNT_MTX(mp), PVFS | PDROP, "vfs_busy", 0);
777 if (flags & MBF_MNTLSTLOCK)
778 mtx_lock(&mountlist_mtx);
781 if (flags & MBF_MNTLSTLOCK)
782 mtx_unlock(&mountlist_mtx);
789 * Free a busy filesystem.
792 vfs_unbusy(struct mount *mp)
796 CTR2(KTR_VFS, "%s: mp %p", __func__, mp);
798 if (vfs_op_thread_enter(mp)) {
799 MPASS((mp->mnt_kern_flag & MNTK_DRAINING) == 0);
800 vfs_mp_count_sub_pcpu(mp, lockref, 1);
801 vfs_mp_count_sub_pcpu(mp, ref, 1);
802 vfs_op_thread_exit(mp);
807 vfs_assert_mount_counters(mp);
809 c = --mp->mnt_lockref;
810 if (mp->mnt_vfs_ops == 0) {
811 MPASS((mp->mnt_kern_flag & MNTK_DRAINING) == 0);
816 vfs_dump_mount_counters(mp);
817 if (c == 0 && (mp->mnt_kern_flag & MNTK_DRAINING) != 0) {
818 MPASS(mp->mnt_kern_flag & MNTK_UNMOUNT);
819 CTR1(KTR_VFS, "%s: waking up waiters", __func__);
820 mp->mnt_kern_flag &= ~MNTK_DRAINING;
821 wakeup(&mp->mnt_lockref);
827 * Lookup a mount point by filesystem identifier.
830 vfs_getvfs(fsid_t *fsid)
834 CTR2(KTR_VFS, "%s: fsid %p", __func__, fsid);
835 mtx_lock(&mountlist_mtx);
836 TAILQ_FOREACH(mp, &mountlist, mnt_list) {
837 if (fsidcmp(&mp->mnt_stat.f_fsid, fsid) == 0) {
839 mtx_unlock(&mountlist_mtx);
843 mtx_unlock(&mountlist_mtx);
844 CTR2(KTR_VFS, "%s: lookup failed for %p id", __func__, fsid);
845 return ((struct mount *) 0);
849 * Lookup a mount point by filesystem identifier, busying it before
852 * To avoid congestion on mountlist_mtx, implement simple direct-mapped
853 * cache for popular filesystem identifiers. The cache is lockess, using
854 * the fact that struct mount's are never freed. In worst case we may
855 * get pointer to unmounted or even different filesystem, so we have to
856 * check what we got, and go slow way if so.
859 vfs_busyfs(fsid_t *fsid)
861 #define FSID_CACHE_SIZE 256
862 typedef struct mount * volatile vmp_t;
863 static vmp_t cache[FSID_CACHE_SIZE];
868 CTR2(KTR_VFS, "%s: fsid %p", __func__, fsid);
869 hash = fsid->val[0] ^ fsid->val[1];
870 hash = (hash >> 16 ^ hash) & (FSID_CACHE_SIZE - 1);
872 if (mp == NULL || fsidcmp(&mp->mnt_stat.f_fsid, fsid) != 0)
874 if (vfs_busy(mp, 0) != 0) {
878 if (fsidcmp(&mp->mnt_stat.f_fsid, fsid) == 0)
884 mtx_lock(&mountlist_mtx);
885 TAILQ_FOREACH(mp, &mountlist, mnt_list) {
886 if (fsidcmp(&mp->mnt_stat.f_fsid, fsid) == 0) {
887 error = vfs_busy(mp, MBF_MNTLSTLOCK);
890 mtx_unlock(&mountlist_mtx);
897 CTR2(KTR_VFS, "%s: lookup failed for %p id", __func__, fsid);
898 mtx_unlock(&mountlist_mtx);
899 return ((struct mount *) 0);
903 * Check if a user can access privileged mount options.
906 vfs_suser(struct mount *mp, struct thread *td)
910 if (jailed(td->td_ucred)) {
912 * If the jail of the calling thread lacks permission for
913 * this type of file system, deny immediately.
915 if (!prison_allow(td->td_ucred, mp->mnt_vfc->vfc_prison_flag))
919 * If the file system was mounted outside the jail of the
920 * calling thread, deny immediately.
922 if (prison_check(td->td_ucred, mp->mnt_cred) != 0)
927 * If file system supports delegated administration, we don't check
928 * for the PRIV_VFS_MOUNT_OWNER privilege - it will be better verified
929 * by the file system itself.
930 * If this is not the user that did original mount, we check for
931 * the PRIV_VFS_MOUNT_OWNER privilege.
933 if (!(mp->mnt_vfc->vfc_flags & VFCF_DELEGADMIN) &&
934 mp->mnt_cred->cr_uid != td->td_ucred->cr_uid) {
935 if ((error = priv_check(td, PRIV_VFS_MOUNT_OWNER)) != 0)
942 * Get a new unique fsid. Try to make its val[0] unique, since this value
943 * will be used to create fake device numbers for stat(). Also try (but
944 * not so hard) make its val[0] unique mod 2^16, since some emulators only
945 * support 16-bit device numbers. We end up with unique val[0]'s for the
946 * first 2^16 calls and unique val[0]'s mod 2^16 for the first 2^8 calls.
948 * Keep in mind that several mounts may be running in parallel. Starting
949 * the search one past where the previous search terminated is both a
950 * micro-optimization and a defense against returning the same fsid to
954 vfs_getnewfsid(struct mount *mp)
956 static uint16_t mntid_base;
961 CTR2(KTR_VFS, "%s: mp %p", __func__, mp);
962 mtx_lock(&mntid_mtx);
963 mtype = mp->mnt_vfc->vfc_typenum;
964 tfsid.val[1] = mtype;
965 mtype = (mtype & 0xFF) << 24;
967 tfsid.val[0] = makedev(255,
968 mtype | ((mntid_base & 0xFF00) << 8) | (mntid_base & 0xFF));
970 if ((nmp = vfs_getvfs(&tfsid)) == NULL)
974 mp->mnt_stat.f_fsid.val[0] = tfsid.val[0];
975 mp->mnt_stat.f_fsid.val[1] = tfsid.val[1];
976 mtx_unlock(&mntid_mtx);
980 * Knob to control the precision of file timestamps:
982 * 0 = seconds only; nanoseconds zeroed.
983 * 1 = seconds and nanoseconds, accurate within 1/HZ.
984 * 2 = seconds and nanoseconds, truncated to microseconds.
985 * >=3 = seconds and nanoseconds, maximum precision.
987 enum { TSP_SEC, TSP_HZ, TSP_USEC, TSP_NSEC };
989 static int timestamp_precision = TSP_USEC;
990 SYSCTL_INT(_vfs, OID_AUTO, timestamp_precision, CTLFLAG_RW,
991 ×tamp_precision, 0, "File timestamp precision (0: seconds, "
992 "1: sec + ns accurate to 1/HZ, 2: sec + ns truncated to us, "
993 "3+: sec + ns (max. precision))");
996 * Get a current timestamp.
999 vfs_timestamp(struct timespec *tsp)
1003 switch (timestamp_precision) {
1005 tsp->tv_sec = time_second;
1013 TIMEVAL_TO_TIMESPEC(&tv, tsp);
1023 * Set vnode attributes to VNOVAL
1026 vattr_null(struct vattr *vap)
1029 vap->va_type = VNON;
1030 vap->va_size = VNOVAL;
1031 vap->va_bytes = VNOVAL;
1032 vap->va_mode = VNOVAL;
1033 vap->va_nlink = VNOVAL;
1034 vap->va_uid = VNOVAL;
1035 vap->va_gid = VNOVAL;
1036 vap->va_fsid = VNOVAL;
1037 vap->va_fileid = VNOVAL;
1038 vap->va_blocksize = VNOVAL;
1039 vap->va_rdev = VNOVAL;
1040 vap->va_atime.tv_sec = VNOVAL;
1041 vap->va_atime.tv_nsec = VNOVAL;
1042 vap->va_mtime.tv_sec = VNOVAL;
1043 vap->va_mtime.tv_nsec = VNOVAL;
1044 vap->va_ctime.tv_sec = VNOVAL;
1045 vap->va_ctime.tv_nsec = VNOVAL;
1046 vap->va_birthtime.tv_sec = VNOVAL;
1047 vap->va_birthtime.tv_nsec = VNOVAL;
1048 vap->va_flags = VNOVAL;
1049 vap->va_gen = VNOVAL;
1050 vap->va_vaflags = 0;
1054 * Try to reduce the total number of vnodes.
1056 * This routine (and its user) are buggy in at least the following ways:
1057 * - all parameters were picked years ago when RAM sizes were significantly
1059 * - it can pick vnodes based on pages used by the vm object, but filesystems
1060 * like ZFS don't use it making the pick broken
1061 * - since ZFS has its own aging policy it gets partially combated by this one
1062 * - a dedicated method should be provided for filesystems to let them decide
1063 * whether the vnode should be recycled
1065 * This routine is called when we have too many vnodes. It attempts
1066 * to free <count> vnodes and will potentially free vnodes that still
1067 * have VM backing store (VM backing store is typically the cause
1068 * of a vnode blowout so we want to do this). Therefore, this operation
1069 * is not considered cheap.
1071 * A number of conditions may prevent a vnode from being reclaimed.
1072 * the buffer cache may have references on the vnode, a directory
1073 * vnode may still have references due to the namei cache representing
1074 * underlying files, or the vnode may be in active use. It is not
1075 * desirable to reuse such vnodes. These conditions may cause the
1076 * number of vnodes to reach some minimum value regardless of what
1077 * you set kern.maxvnodes to. Do not set kern.maxvnodes too low.
1079 * @param reclaim_nc_src Only reclaim directories with outgoing namecache
1080 * entries if this argument is strue
1081 * @param trigger Only reclaim vnodes with fewer than this many resident
1083 * @param target How many vnodes to reclaim.
1084 * @return The number of vnodes that were reclaimed.
1087 vlrureclaim(bool reclaim_nc_src, int trigger, u_long target)
1089 struct vnode *vp, *mvp;
1091 struct vm_object *object;
1095 mtx_assert(&vnode_list_mtx, MA_OWNED);
1100 mvp = vnode_list_reclaim_marker;
1103 while (done < target) {
1104 vp = TAILQ_NEXT(vp, v_vnodelist);
1105 if (__predict_false(vp == NULL))
1108 if (__predict_false(vp->v_type == VMARKER))
1112 * If it's been deconstructed already, it's still
1113 * referenced, or it exceeds the trigger, skip it.
1114 * Also skip free vnodes. We are trying to make space
1115 * to expand the free list, not reduce it.
1117 if (vp->v_usecount > 0 || vp->v_holdcnt == 0 ||
1118 (!reclaim_nc_src && !LIST_EMPTY(&vp->v_cache_src)))
1121 if (vp->v_type == VBAD || vp->v_type == VNON)
1124 if (!VI_TRYLOCK(vp))
1127 if (vp->v_usecount > 0 || vp->v_holdcnt == 0 ||
1128 (!reclaim_nc_src && !LIST_EMPTY(&vp->v_cache_src)) ||
1129 VN_IS_DOOMED(vp) || vp->v_type == VNON) {
1134 object = atomic_load_ptr(&vp->v_object);
1135 if (object == NULL || object->resident_page_count > trigger) {
1142 TAILQ_REMOVE(&vnode_list, mvp, v_vnodelist);
1143 TAILQ_INSERT_AFTER(&vnode_list, vp, mvp, v_vnodelist);
1144 mtx_unlock(&vnode_list_mtx);
1146 if (vn_start_write(vp, &mp, V_NOWAIT) != 0) {
1148 goto next_iter_unlocked;
1150 if (VOP_LOCK(vp, LK_EXCLUSIVE|LK_NOWAIT) != 0) {
1152 vn_finished_write(mp);
1153 goto next_iter_unlocked;
1157 if (vp->v_usecount > 0 ||
1158 (!reclaim_nc_src && !LIST_EMPTY(&vp->v_cache_src)) ||
1159 (vp->v_object != NULL &&
1160 vp->v_object->resident_page_count > trigger)) {
1163 vn_finished_write(mp);
1164 goto next_iter_unlocked;
1166 counter_u64_add(recycles_count, 1);
1170 vn_finished_write(mp);
1174 kern_yield(PRI_USER);
1175 mtx_lock(&vnode_list_mtx);
1178 MPASS(vp->v_type != VMARKER);
1179 if (!should_yield())
1181 TAILQ_REMOVE(&vnode_list, mvp, v_vnodelist);
1182 TAILQ_INSERT_AFTER(&vnode_list, vp, mvp, v_vnodelist);
1183 mtx_unlock(&vnode_list_mtx);
1184 kern_yield(PRI_USER);
1185 mtx_lock(&vnode_list_mtx);
1188 if (done == 0 && !retried) {
1189 TAILQ_REMOVE(&vnode_list, mvp, v_vnodelist);
1190 TAILQ_INSERT_HEAD(&vnode_list, mvp, v_vnodelist);
1197 static int max_vnlru_free = 10000; /* limit on vnode free requests per call */
1198 SYSCTL_INT(_debug, OID_AUTO, max_vnlru_free, CTLFLAG_RW, &max_vnlru_free,
1200 "limit on vnode free requests per call to the vnlru_free routine");
1203 * Attempt to reduce the free list by the requested amount.
1206 vnlru_free_locked(int count, struct vfsops *mnt_op)
1208 struct vnode *vp, *mvp;
1212 mtx_assert(&vnode_list_mtx, MA_OWNED);
1213 if (count > max_vnlru_free)
1214 count = max_vnlru_free;
1216 mvp = vnode_list_free_marker;
1220 vp = TAILQ_NEXT(vp, v_vnodelist);
1221 if (__predict_false(vp == NULL)) {
1222 TAILQ_REMOVE(&vnode_list, mvp, v_vnodelist);
1223 TAILQ_INSERT_TAIL(&vnode_list, mvp, v_vnodelist);
1226 if (__predict_false(vp->v_type == VMARKER))
1230 * Don't recycle if our vnode is from different type
1231 * of mount point. Note that mp is type-safe, the
1232 * check does not reach unmapped address even if
1233 * vnode is reclaimed.
1234 * Don't recycle if we can't get the interlock without
1237 if (vp->v_holdcnt > 0 || (mnt_op != NULL && (mp = vp->v_mount) != NULL &&
1238 mp->mnt_op != mnt_op) || !VI_TRYLOCK(vp)) {
1241 TAILQ_REMOVE(&vnode_list, mvp, v_vnodelist);
1242 TAILQ_INSERT_AFTER(&vnode_list, vp, mvp, v_vnodelist);
1243 if (__predict_false(vp->v_type == VBAD || vp->v_type == VNON)) {
1249 mtx_unlock(&vnode_list_mtx);
1253 mtx_lock(&vnode_list_mtx);
1256 return (ocount - count);
1260 vnlru_free(int count, struct vfsops *mnt_op)
1263 mtx_lock(&vnode_list_mtx);
1264 vnlru_free_locked(count, mnt_op);
1265 mtx_unlock(&vnode_list_mtx);
1272 mtx_assert(&vnode_list_mtx, MA_OWNED);
1273 gapvnodes = imax(desiredvnodes - wantfreevnodes, 100);
1274 vhiwat = gapvnodes / 11; /* 9% -- just under the 10% in vlrureclaim() */
1275 vlowat = vhiwat / 2;
1279 * Attempt to recycle vnodes in a context that is always safe to block.
1280 * Calling vlrurecycle() from the bowels of filesystem code has some
1281 * interesting deadlock problems.
1283 static struct proc *vnlruproc;
1284 static int vnlruproc_sig;
1287 * The main freevnodes counter is only updated when threads requeue their vnode
1288 * batches. CPUs are conditionally walked to compute a more accurate total.
1290 * Limit how much of a slop are we willing to tolerate. Note: the actual value
1291 * at any given moment can still exceed slop, but it should not be by significant
1292 * margin in practice.
1294 #define VNLRU_FREEVNODES_SLOP 128
1297 vnlru_read_freevnodes(void)
1303 mtx_assert(&vnode_list_mtx, MA_OWNED);
1304 if (freevnodes > freevnodes_old)
1305 slop = freevnodes - freevnodes_old;
1307 slop = freevnodes_old - freevnodes;
1308 if (slop < VNLRU_FREEVNODES_SLOP)
1309 return (freevnodes >= 0 ? freevnodes : 0);
1310 freevnodes_old = freevnodes;
1312 vd = DPCPU_ID_PTR((cpu), vd);
1313 freevnodes_old += vd->freevnodes;
1315 return (freevnodes_old >= 0 ? freevnodes_old : 0);
1319 vnlru_under(u_long rnumvnodes, u_long limit)
1321 u_long rfreevnodes, space;
1323 if (__predict_false(rnumvnodes > desiredvnodes))
1326 space = desiredvnodes - rnumvnodes;
1327 if (space < limit) {
1328 rfreevnodes = vnlru_read_freevnodes();
1329 if (rfreevnodes > wantfreevnodes)
1330 space += rfreevnodes - wantfreevnodes;
1332 return (space < limit);
1336 vnlru_under_unlocked(u_long rnumvnodes, u_long limit)
1338 long rfreevnodes, space;
1340 if (__predict_false(rnumvnodes > desiredvnodes))
1343 space = desiredvnodes - rnumvnodes;
1344 if (space < limit) {
1345 rfreevnodes = atomic_load_long(&freevnodes);
1346 if (rfreevnodes > wantfreevnodes)
1347 space += rfreevnodes - wantfreevnodes;
1349 return (space < limit);
1356 mtx_assert(&vnode_list_mtx, MA_OWNED);
1357 if (vnlruproc_sig == 0) {
1366 u_long rnumvnodes, rfreevnodes, target;
1367 unsigned long onumvnodes;
1368 int done, force, trigger, usevnodes;
1369 bool reclaim_nc_src, want_reread;
1371 EVENTHANDLER_REGISTER(shutdown_pre_sync, kproc_shutdown, vnlruproc,
1372 SHUTDOWN_PRI_FIRST);
1375 want_reread = false;
1377 kproc_suspend_check(vnlruproc);
1378 mtx_lock(&vnode_list_mtx);
1379 rnumvnodes = atomic_load_long(&numvnodes);
1382 force = vnlru_under(numvnodes, vhiwat) ? 1 : 0;
1383 want_reread = false;
1387 * If numvnodes is too large (due to desiredvnodes being
1388 * adjusted using its sysctl, or emergency growth), first
1389 * try to reduce it by discarding from the free list.
1391 if (rnumvnodes > desiredvnodes) {
1392 vnlru_free_locked(rnumvnodes - desiredvnodes, NULL);
1393 rnumvnodes = atomic_load_long(&numvnodes);
1396 * Sleep if the vnode cache is in a good state. This is
1397 * when it is not over-full and has space for about a 4%
1398 * or 9% expansion (by growing its size or inexcessively
1399 * reducing its free list). Otherwise, try to reclaim
1400 * space for a 10% expansion.
1402 if (vstir && force == 0) {
1406 if (force == 0 && !vnlru_under(rnumvnodes, vlowat)) {
1408 wakeup(&vnlruproc_sig);
1409 msleep(vnlruproc, &vnode_list_mtx,
1410 PVFS|PDROP, "vlruwt", hz);
1413 rfreevnodes = vnlru_read_freevnodes();
1415 onumvnodes = rnumvnodes;
1417 * Calculate parameters for recycling. These are the same
1418 * throughout the loop to give some semblance of fairness.
1419 * The trigger point is to avoid recycling vnodes with lots
1420 * of resident pages. We aren't trying to free memory; we
1421 * are trying to recycle or at least free vnodes.
1423 if (rnumvnodes <= desiredvnodes)
1424 usevnodes = rnumvnodes - rfreevnodes;
1426 usevnodes = rnumvnodes;
1430 * The trigger value is is chosen to give a conservatively
1431 * large value to ensure that it alone doesn't prevent
1432 * making progress. The value can easily be so large that
1433 * it is effectively infinite in some congested and
1434 * misconfigured cases, and this is necessary. Normally
1435 * it is about 8 to 100 (pages), which is quite large.
1437 trigger = vm_cnt.v_page_count * 2 / usevnodes;
1439 trigger = vsmalltrigger;
1440 reclaim_nc_src = force >= 3;
1441 target = rnumvnodes * (int64_t)gapvnodes / imax(desiredvnodes, 1);
1442 target = target / 10 + 1;
1443 done = vlrureclaim(reclaim_nc_src, trigger, target);
1444 mtx_unlock(&vnode_list_mtx);
1445 if (onumvnodes > desiredvnodes && numvnodes <= desiredvnodes)
1446 uma_reclaim(UMA_RECLAIM_DRAIN);
1448 if (force == 0 || force == 1) {
1459 tsleep(vnlruproc, PPAUSE, "vlrup", hz * 3);
1462 kern_yield(PRI_USER);
1467 static struct kproc_desc vnlru_kp = {
1472 SYSINIT(vnlru, SI_SUB_KTHREAD_UPDATE, SI_ORDER_FIRST, kproc_start,
1476 * Routines having to do with the management of the vnode table.
1480 * Try to recycle a freed vnode. We abort if anyone picks up a reference
1481 * before we actually vgone(). This function must be called with the vnode
1482 * held to prevent the vnode from being returned to the free list midway
1486 vtryrecycle(struct vnode *vp)
1490 CTR2(KTR_VFS, "%s: vp %p", __func__, vp);
1491 VNASSERT(vp->v_holdcnt, vp,
1492 ("vtryrecycle: Recycling vp %p without a reference.", vp));
1494 * This vnode may found and locked via some other list, if so we
1495 * can't recycle it yet.
1497 if (VOP_LOCK(vp, LK_EXCLUSIVE | LK_NOWAIT) != 0) {
1499 "%s: impossible to recycle, vp %p lock is already held",
1501 return (EWOULDBLOCK);
1504 * Don't recycle if its filesystem is being suspended.
1506 if (vn_start_write(vp, &vnmp, V_NOWAIT) != 0) {
1509 "%s: impossible to recycle, cannot start the write for %p",
1514 * If we got this far, we need to acquire the interlock and see if
1515 * anyone picked up this vnode from another list. If not, we will
1516 * mark it with DOOMED via vgonel() so that anyone who does find it
1517 * will skip over it.
1520 if (vp->v_usecount) {
1523 vn_finished_write(vnmp);
1525 "%s: impossible to recycle, %p is already referenced",
1529 if (!VN_IS_DOOMED(vp)) {
1530 counter_u64_add(recycles_free_count, 1);
1535 vn_finished_write(vnmp);
1540 * Allocate a new vnode.
1542 * The operation never returns an error. Returning an error was disabled
1543 * in r145385 (dated 2005) with the following comment:
1545 * XXX Not all VFS_VGET/ffs_vget callers check returns.
1547 * Given the age of this commit (almost 15 years at the time of writing this
1548 * comment) restoring the ability to fail requires a significant audit of
1551 * The routine can try to free a vnode or stall for up to 1 second waiting for
1552 * vnlru to clear things up, but ultimately always performs a M_WAITOK allocation.
1554 static u_long vn_alloc_cyclecount;
1556 static struct vnode * __noinline
1557 vn_alloc_hard(struct mount *mp)
1559 u_long rnumvnodes, rfreevnodes;
1561 mtx_lock(&vnode_list_mtx);
1562 rnumvnodes = atomic_load_long(&numvnodes);
1563 if (rnumvnodes + 1 < desiredvnodes) {
1564 vn_alloc_cyclecount = 0;
1567 rfreevnodes = vnlru_read_freevnodes();
1568 if (vn_alloc_cyclecount++ >= rfreevnodes) {
1569 vn_alloc_cyclecount = 0;
1573 * Grow the vnode cache if it will not be above its target max
1574 * after growing. Otherwise, if the free list is nonempty, try
1575 * to reclaim 1 item from it before growing the cache (possibly
1576 * above its target max if the reclamation failed or is delayed).
1577 * Otherwise, wait for some space. In all cases, schedule
1578 * vnlru_proc() if we are getting short of space. The watermarks
1579 * should be chosen so that we never wait or even reclaim from
1580 * the free list to below its target minimum.
1582 if (vnlru_free_locked(1, NULL) > 0)
1584 if (mp == NULL || (mp->mnt_kern_flag & MNTK_SUSPEND) == 0) {
1586 * Wait for space for a new vnode.
1589 msleep(&vnlruproc_sig, &vnode_list_mtx, PVFS, "vlruwk", hz);
1590 if (atomic_load_long(&numvnodes) + 1 > desiredvnodes &&
1591 vnlru_read_freevnodes() > 1)
1592 vnlru_free_locked(1, NULL);
1595 rnumvnodes = atomic_fetchadd_long(&numvnodes, 1) + 1;
1596 if (vnlru_under(rnumvnodes, vlowat))
1598 mtx_unlock(&vnode_list_mtx);
1599 return (uma_zalloc_smr(vnode_zone, M_WAITOK));
1602 static struct vnode *
1603 vn_alloc(struct mount *mp)
1607 if (__predict_false(vn_alloc_cyclecount != 0))
1608 return (vn_alloc_hard(mp));
1609 rnumvnodes = atomic_fetchadd_long(&numvnodes, 1) + 1;
1610 if (__predict_false(vnlru_under_unlocked(rnumvnodes, vlowat))) {
1611 atomic_subtract_long(&numvnodes, 1);
1612 return (vn_alloc_hard(mp));
1615 return (uma_zalloc_smr(vnode_zone, M_WAITOK));
1619 vn_free(struct vnode *vp)
1622 atomic_subtract_long(&numvnodes, 1);
1623 uma_zfree_smr(vnode_zone, vp);
1627 * Return the next vnode from the free list.
1630 getnewvnode(const char *tag, struct mount *mp, struct vop_vector *vops,
1635 struct lock_object *lo;
1637 CTR3(KTR_VFS, "%s: mp %p with tag %s", __func__, mp, tag);
1639 KASSERT(vops->registered,
1640 ("%s: not registered vector op %p\n", __func__, vops));
1643 if (td->td_vp_reserved != NULL) {
1644 vp = td->td_vp_reserved;
1645 td->td_vp_reserved = NULL;
1649 counter_u64_add(vnodes_created, 1);
1651 * Locks are given the generic name "vnode" when created.
1652 * Follow the historic practice of using the filesystem
1653 * name when they allocated, e.g., "zfs", "ufs", "nfs, etc.
1655 * Locks live in a witness group keyed on their name. Thus,
1656 * when a lock is renamed, it must also move from the witness
1657 * group of its old name to the witness group of its new name.
1659 * The change only needs to be made when the vnode moves
1660 * from one filesystem type to another. We ensure that each
1661 * filesystem use a single static name pointer for its tag so
1662 * that we can compare pointers rather than doing a strcmp().
1664 lo = &vp->v_vnlock->lock_object;
1666 if (lo->lo_name != tag) {
1670 WITNESS_DESTROY(lo);
1671 WITNESS_INIT(lo, tag);
1675 * By default, don't allow shared locks unless filesystems opt-in.
1677 vp->v_vnlock->lock_object.lo_flags |= LK_NOSHARE;
1679 * Finalize various vnode identity bits.
1681 KASSERT(vp->v_object == NULL, ("stale v_object %p", vp));
1682 KASSERT(vp->v_lockf == NULL, ("stale v_lockf %p", vp));
1683 KASSERT(vp->v_pollinfo == NULL, ("stale v_pollinfo %p", vp));
1686 v_init_counters(vp);
1687 vp->v_bufobj.bo_ops = &buf_ops_bio;
1689 if (mp == NULL && vops != &dead_vnodeops)
1690 printf("NULL mp in getnewvnode(9), tag %s\n", tag);
1694 if (mp != NULL && (mp->mnt_flag & MNT_MULTILABEL) == 0)
1695 mac_vnode_associate_singlelabel(mp, vp);
1698 vp->v_bufobj.bo_bsize = mp->mnt_stat.f_iosize;
1699 if ((mp->mnt_kern_flag & MNTK_NOKNOTE) != 0)
1700 vp->v_vflag |= VV_NOKNOTE;
1704 * For the filesystems which do not use vfs_hash_insert(),
1705 * still initialize v_hash to have vfs_hash_index() useful.
1706 * E.g., nullfs uses vfs_hash_index() on the lower vnode for
1709 vp->v_hash = (uintptr_t)vp >> vnsz2log;
1716 getnewvnode_reserve(void)
1721 MPASS(td->td_vp_reserved == NULL);
1722 td->td_vp_reserved = vn_alloc(NULL);
1726 getnewvnode_drop_reserve(void)
1731 if (td->td_vp_reserved != NULL) {
1732 vn_free(td->td_vp_reserved);
1733 td->td_vp_reserved = NULL;
1738 freevnode(struct vnode *vp)
1743 * The vnode has been marked for destruction, so free it.
1745 * The vnode will be returned to the zone where it will
1746 * normally remain until it is needed for another vnode. We
1747 * need to cleanup (or verify that the cleanup has already
1748 * been done) any residual data left from its current use
1749 * so as not to contaminate the freshly allocated vnode.
1751 CTR2(KTR_VFS, "%s: destroying the vnode %p", __func__, vp);
1753 * Paired with vgone.
1755 vn_seqc_write_end_locked(vp);
1756 VNPASS(vp->v_seqc_users == 0, vp);
1759 VNASSERT(vp->v_data == NULL, vp, ("cleaned vnode isn't"));
1760 VNPASS(vp->v_holdcnt == VHOLD_NO_SMR, vp);
1761 VNASSERT(vp->v_usecount == 0, vp, ("Non-zero use count"));
1762 VNASSERT(vp->v_writecount == 0, vp, ("Non-zero write count"));
1763 VNASSERT(bo->bo_numoutput == 0, vp, ("Clean vnode has pending I/O's"));
1764 VNASSERT(bo->bo_clean.bv_cnt == 0, vp, ("cleanbufcnt not 0"));
1765 VNASSERT(pctrie_is_empty(&bo->bo_clean.bv_root), vp,
1766 ("clean blk trie not empty"));
1767 VNASSERT(bo->bo_dirty.bv_cnt == 0, vp, ("dirtybufcnt not 0"));
1768 VNASSERT(pctrie_is_empty(&bo->bo_dirty.bv_root), vp,
1769 ("dirty blk trie not empty"));
1770 VNASSERT(TAILQ_EMPTY(&vp->v_cache_dst), vp, ("vp has namecache dst"));
1771 VNASSERT(LIST_EMPTY(&vp->v_cache_src), vp, ("vp has namecache src"));
1772 VNASSERT(vp->v_cache_dd == NULL, vp, ("vp has namecache for .."));
1773 VNASSERT(TAILQ_EMPTY(&vp->v_rl.rl_waiters), vp,
1774 ("Dangling rangelock waiters"));
1777 mac_vnode_destroy(vp);
1779 if (vp->v_pollinfo != NULL) {
1780 destroy_vpollinfo(vp->v_pollinfo);
1781 vp->v_pollinfo = NULL;
1784 /* XXX Elsewhere we detect an already freed vnode via NULL v_op. */
1787 vp->v_mountedhere = NULL;
1790 vp->v_fifoinfo = NULL;
1791 vp->v_lasta = vp->v_clen = vp->v_cstart = vp->v_lastw = 0;
1800 * Delete from old mount point vnode list, if on one.
1803 delmntque(struct vnode *vp)
1807 VNPASS((vp->v_mflag & VMP_LAZYLIST) == 0, vp);
1816 VNASSERT(mp->mnt_nvnodelistsize > 0, vp,
1817 ("bad mount point vnode list size"));
1818 TAILQ_REMOVE(&mp->mnt_nvnodelist, vp, v_nmntvnodes);
1819 mp->mnt_nvnodelistsize--;
1825 insmntque_stddtr(struct vnode *vp, void *dtr_arg)
1829 vp->v_op = &dead_vnodeops;
1835 * Insert into list of vnodes for the new mount point, if available.
1838 insmntque1(struct vnode *vp, struct mount *mp,
1839 void (*dtr)(struct vnode *, void *), void *dtr_arg)
1842 KASSERT(vp->v_mount == NULL,
1843 ("insmntque: vnode already on per mount vnode list"));
1844 VNASSERT(mp != NULL, vp, ("Don't call insmntque(foo, NULL)"));
1845 ASSERT_VOP_ELOCKED(vp, "insmntque: non-locked vp");
1848 * We acquire the vnode interlock early to ensure that the
1849 * vnode cannot be recycled by another process releasing a
1850 * holdcnt on it before we get it on both the vnode list
1851 * and the active vnode list. The mount mutex protects only
1852 * manipulation of the vnode list and the vnode freelist
1853 * mutex protects only manipulation of the active vnode list.
1854 * Hence the need to hold the vnode interlock throughout.
1858 if (((mp->mnt_kern_flag & MNTK_UNMOUNT) != 0 &&
1859 ((mp->mnt_kern_flag & MNTK_UNMOUNTF) != 0 ||
1860 mp->mnt_nvnodelistsize == 0)) &&
1861 (vp->v_vflag & VV_FORCEINSMQ) == 0) {
1870 TAILQ_INSERT_TAIL(&mp->mnt_nvnodelist, vp, v_nmntvnodes);
1871 VNASSERT(mp->mnt_nvnodelistsize >= 0, vp,
1872 ("neg mount point vnode list size"));
1873 mp->mnt_nvnodelistsize++;
1880 insmntque(struct vnode *vp, struct mount *mp)
1883 return (insmntque1(vp, mp, insmntque_stddtr, NULL));
1887 * Flush out and invalidate all buffers associated with a bufobj
1888 * Called with the underlying object locked.
1891 bufobj_invalbuf(struct bufobj *bo, int flags, int slpflag, int slptimeo)
1896 if (flags & V_SAVE) {
1897 error = bufobj_wwait(bo, slpflag, slptimeo);
1902 if (bo->bo_dirty.bv_cnt > 0) {
1904 if ((error = BO_SYNC(bo, MNT_WAIT)) != 0)
1907 * XXX We could save a lock/unlock if this was only
1908 * enabled under INVARIANTS
1911 if (bo->bo_numoutput > 0 || bo->bo_dirty.bv_cnt > 0)
1912 panic("vinvalbuf: dirty bufs");
1916 * If you alter this loop please notice that interlock is dropped and
1917 * reacquired in flushbuflist. Special care is needed to ensure that
1918 * no race conditions occur from this.
1921 error = flushbuflist(&bo->bo_clean,
1922 flags, bo, slpflag, slptimeo);
1923 if (error == 0 && !(flags & V_CLEANONLY))
1924 error = flushbuflist(&bo->bo_dirty,
1925 flags, bo, slpflag, slptimeo);
1926 if (error != 0 && error != EAGAIN) {
1930 } while (error != 0);
1933 * Wait for I/O to complete. XXX needs cleaning up. The vnode can
1934 * have write I/O in-progress but if there is a VM object then the
1935 * VM object can also have read-I/O in-progress.
1938 bufobj_wwait(bo, 0, 0);
1939 if ((flags & V_VMIO) == 0 && bo->bo_object != NULL) {
1941 vm_object_pip_wait_unlocked(bo->bo_object, "bovlbx");
1944 } while (bo->bo_numoutput > 0);
1948 * Destroy the copy in the VM cache, too.
1950 if (bo->bo_object != NULL &&
1951 (flags & (V_ALT | V_NORMAL | V_CLEANONLY | V_VMIO)) == 0) {
1952 VM_OBJECT_WLOCK(bo->bo_object);
1953 vm_object_page_remove(bo->bo_object, 0, 0, (flags & V_SAVE) ?
1954 OBJPR_CLEANONLY : 0);
1955 VM_OBJECT_WUNLOCK(bo->bo_object);
1960 if ((flags & (V_ALT | V_NORMAL | V_CLEANONLY | V_VMIO |
1961 V_ALLOWCLEAN)) == 0 && (bo->bo_dirty.bv_cnt > 0 ||
1962 bo->bo_clean.bv_cnt > 0))
1963 panic("vinvalbuf: flush failed");
1964 if ((flags & (V_ALT | V_NORMAL | V_CLEANONLY | V_VMIO)) == 0 &&
1965 bo->bo_dirty.bv_cnt > 0)
1966 panic("vinvalbuf: flush dirty failed");
1973 * Flush out and invalidate all buffers associated with a vnode.
1974 * Called with the underlying object locked.
1977 vinvalbuf(struct vnode *vp, int flags, int slpflag, int slptimeo)
1980 CTR3(KTR_VFS, "%s: vp %p with flags %d", __func__, vp, flags);
1981 ASSERT_VOP_LOCKED(vp, "vinvalbuf");
1982 if (vp->v_object != NULL && vp->v_object->handle != vp)
1984 return (bufobj_invalbuf(&vp->v_bufobj, flags, slpflag, slptimeo));
1988 * Flush out buffers on the specified list.
1992 flushbuflist(struct bufv *bufv, int flags, struct bufobj *bo, int slpflag,
1995 struct buf *bp, *nbp;
2000 ASSERT_BO_WLOCKED(bo);
2003 TAILQ_FOREACH_SAFE(bp, &bufv->bv_hd, b_bobufs, nbp) {
2005 * If we are flushing both V_NORMAL and V_ALT buffers then
2006 * do not skip any buffers. If we are flushing only V_NORMAL
2007 * buffers then skip buffers marked as BX_ALTDATA. If we are
2008 * flushing only V_ALT buffers then skip buffers not marked
2011 if (((flags & (V_NORMAL | V_ALT)) != (V_NORMAL | V_ALT)) &&
2012 (((flags & V_NORMAL) && (bp->b_xflags & BX_ALTDATA) != 0) ||
2013 ((flags & V_ALT) && (bp->b_xflags & BX_ALTDATA) == 0))) {
2017 lblkno = nbp->b_lblkno;
2018 xflags = nbp->b_xflags & (BX_VNDIRTY | BX_VNCLEAN);
2021 error = BUF_TIMELOCK(bp,
2022 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK, BO_LOCKPTR(bo),
2023 "flushbuf", slpflag, slptimeo);
2026 return (error != ENOLCK ? error : EAGAIN);
2028 KASSERT(bp->b_bufobj == bo,
2029 ("bp %p wrong b_bufobj %p should be %p",
2030 bp, bp->b_bufobj, bo));
2032 * XXX Since there are no node locks for NFS, I
2033 * believe there is a slight chance that a delayed
2034 * write will occur while sleeping just above, so
2037 if (((bp->b_flags & (B_DELWRI | B_INVAL)) == B_DELWRI) &&
2040 bp->b_flags |= B_ASYNC;
2043 return (EAGAIN); /* XXX: why not loop ? */
2046 bp->b_flags |= (B_INVAL | B_RELBUF);
2047 bp->b_flags &= ~B_ASYNC;
2052 nbp = gbincore(bo, lblkno);
2053 if (nbp == NULL || (nbp->b_xflags & (BX_VNDIRTY | BX_VNCLEAN))
2055 break; /* nbp invalid */
2061 bnoreuselist(struct bufv *bufv, struct bufobj *bo, daddr_t startn, daddr_t endn)
2067 ASSERT_BO_LOCKED(bo);
2069 for (lblkno = startn;;) {
2071 bp = BUF_PCTRIE_LOOKUP_GE(&bufv->bv_root, lblkno);
2072 if (bp == NULL || bp->b_lblkno >= endn ||
2073 bp->b_lblkno < startn)
2075 error = BUF_TIMELOCK(bp, LK_EXCLUSIVE | LK_SLEEPFAIL |
2076 LK_INTERLOCK, BO_LOCKPTR(bo), "brlsfl", 0, 0);
2079 if (error == ENOLCK)
2083 KASSERT(bp->b_bufobj == bo,
2084 ("bp %p wrong b_bufobj %p should be %p",
2085 bp, bp->b_bufobj, bo));
2086 lblkno = bp->b_lblkno + 1;
2087 if ((bp->b_flags & B_MANAGED) == 0)
2089 bp->b_flags |= B_RELBUF;
2091 * In the VMIO case, use the B_NOREUSE flag to hint that the
2092 * pages backing each buffer in the range are unlikely to be
2093 * reused. Dirty buffers will have the hint applied once
2094 * they've been written.
2096 if ((bp->b_flags & B_VMIO) != 0)
2097 bp->b_flags |= B_NOREUSE;
2105 * Truncate a file's buffer and pages to a specified length. This
2106 * is in lieu of the old vinvalbuf mechanism, which performed unneeded
2110 vtruncbuf(struct vnode *vp, off_t length, int blksize)
2112 struct buf *bp, *nbp;
2116 CTR4(KTR_VFS, "%s: vp %p with block %d:%ju", __func__,
2117 vp, blksize, (uintmax_t)length);
2120 * Round up to the *next* lbn.
2122 startlbn = howmany(length, blksize);
2124 ASSERT_VOP_LOCKED(vp, "vtruncbuf");
2130 while (v_inval_buf_range_locked(vp, bo, startlbn, INT64_MAX) == EAGAIN)
2135 TAILQ_FOREACH_SAFE(bp, &bo->bo_dirty.bv_hd, b_bobufs, nbp) {
2136 if (bp->b_lblkno > 0)
2139 * Since we hold the vnode lock this should only
2140 * fail if we're racing with the buf daemon.
2143 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK,
2144 BO_LOCKPTR(bo)) == ENOLCK)
2145 goto restart_unlocked;
2147 VNASSERT((bp->b_flags & B_DELWRI), vp,
2148 ("buf(%p) on dirty queue without DELWRI", bp));
2157 bufobj_wwait(bo, 0, 0);
2159 vnode_pager_setsize(vp, length);
2165 * Invalidate the cached pages of a file's buffer within the range of block
2166 * numbers [startlbn, endlbn).
2169 v_inval_buf_range(struct vnode *vp, daddr_t startlbn, daddr_t endlbn,
2175 ASSERT_VOP_LOCKED(vp, "v_inval_buf_range");
2177 start = blksize * startlbn;
2178 end = blksize * endlbn;
2182 MPASS(blksize == bo->bo_bsize);
2184 while (v_inval_buf_range_locked(vp, bo, startlbn, endlbn) == EAGAIN)
2188 vn_pages_remove(vp, OFF_TO_IDX(start), OFF_TO_IDX(end + PAGE_SIZE - 1));
2192 v_inval_buf_range_locked(struct vnode *vp, struct bufobj *bo,
2193 daddr_t startlbn, daddr_t endlbn)
2195 struct buf *bp, *nbp;
2198 ASSERT_VOP_LOCKED(vp, "v_inval_buf_range_locked");
2199 ASSERT_BO_LOCKED(bo);
2203 TAILQ_FOREACH_SAFE(bp, &bo->bo_clean.bv_hd, b_bobufs, nbp) {
2204 if (bp->b_lblkno < startlbn || bp->b_lblkno >= endlbn)
2207 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK,
2208 BO_LOCKPTR(bo)) == ENOLCK) {
2214 bp->b_flags |= B_INVAL | B_RELBUF;
2215 bp->b_flags &= ~B_ASYNC;
2221 (((nbp->b_xflags & BX_VNCLEAN) == 0) ||
2223 (nbp->b_flags & B_DELWRI) != 0))
2227 TAILQ_FOREACH_SAFE(bp, &bo->bo_dirty.bv_hd, b_bobufs, nbp) {
2228 if (bp->b_lblkno < startlbn || bp->b_lblkno >= endlbn)
2231 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK,
2232 BO_LOCKPTR(bo)) == ENOLCK) {
2237 bp->b_flags |= B_INVAL | B_RELBUF;
2238 bp->b_flags &= ~B_ASYNC;
2244 (((nbp->b_xflags & BX_VNDIRTY) == 0) ||
2245 (nbp->b_vp != vp) ||
2246 (nbp->b_flags & B_DELWRI) == 0))
2254 buf_vlist_remove(struct buf *bp)
2259 flags = bp->b_xflags;
2261 KASSERT(bp->b_bufobj != NULL, ("No b_bufobj %p", bp));
2262 ASSERT_BO_WLOCKED(bp->b_bufobj);
2263 KASSERT((flags & (BX_VNDIRTY | BX_VNCLEAN)) != 0 &&
2264 (flags & (BX_VNDIRTY | BX_VNCLEAN)) != (BX_VNDIRTY | BX_VNCLEAN),
2265 ("%s: buffer %p has invalid queue state", __func__, bp));
2267 if ((flags & BX_VNDIRTY) != 0)
2268 bv = &bp->b_bufobj->bo_dirty;
2270 bv = &bp->b_bufobj->bo_clean;
2271 BUF_PCTRIE_REMOVE(&bv->bv_root, bp->b_lblkno);
2272 TAILQ_REMOVE(&bv->bv_hd, bp, b_bobufs);
2274 bp->b_xflags &= ~(BX_VNDIRTY | BX_VNCLEAN);
2278 * Add the buffer to the sorted clean or dirty block list.
2280 * NOTE: xflags is passed as a constant, optimizing this inline function!
2283 buf_vlist_add(struct buf *bp, struct bufobj *bo, b_xflags_t xflags)
2289 ASSERT_BO_WLOCKED(bo);
2290 KASSERT((bo->bo_flag & BO_NOBUFS) == 0,
2291 ("buf_vlist_add: bo %p does not allow bufs", bo));
2292 KASSERT((xflags & BX_VNDIRTY) == 0 || (bo->bo_flag & BO_DEAD) == 0,
2293 ("dead bo %p", bo));
2294 KASSERT((bp->b_xflags & (BX_VNDIRTY|BX_VNCLEAN)) == 0,
2295 ("buf_vlist_add: Buf %p has existing xflags %d", bp, bp->b_xflags));
2296 bp->b_xflags |= xflags;
2297 if (xflags & BX_VNDIRTY)
2303 * Keep the list ordered. Optimize empty list insertion. Assume
2304 * we tend to grow at the tail so lookup_le should usually be cheaper
2307 if (bv->bv_cnt == 0 ||
2308 bp->b_lblkno > TAILQ_LAST(&bv->bv_hd, buflists)->b_lblkno)
2309 TAILQ_INSERT_TAIL(&bv->bv_hd, bp, b_bobufs);
2310 else if ((n = BUF_PCTRIE_LOOKUP_LE(&bv->bv_root, bp->b_lblkno)) == NULL)
2311 TAILQ_INSERT_HEAD(&bv->bv_hd, bp, b_bobufs);
2313 TAILQ_INSERT_AFTER(&bv->bv_hd, n, bp, b_bobufs);
2314 error = BUF_PCTRIE_INSERT(&bv->bv_root, bp);
2316 panic("buf_vlist_add: Preallocated nodes insufficient.");
2321 * Look up a buffer using the buffer tries.
2324 gbincore(struct bufobj *bo, daddr_t lblkno)
2328 ASSERT_BO_LOCKED(bo);
2329 bp = BUF_PCTRIE_LOOKUP(&bo->bo_clean.bv_root, lblkno);
2332 return (BUF_PCTRIE_LOOKUP(&bo->bo_dirty.bv_root, lblkno));
2336 * Look up a buf using the buffer tries, without the bufobj lock. This relies
2337 * on SMR for safe lookup, and bufs being in a no-free zone to provide type
2338 * stability of the result. Like other lockless lookups, the found buf may
2339 * already be invalid by the time this function returns.
2342 gbincore_unlocked(struct bufobj *bo, daddr_t lblkno)
2346 ASSERT_BO_UNLOCKED(bo);
2347 bp = BUF_PCTRIE_LOOKUP_UNLOCKED(&bo->bo_clean.bv_root, lblkno);
2350 return (BUF_PCTRIE_LOOKUP_UNLOCKED(&bo->bo_dirty.bv_root, lblkno));
2354 * Associate a buffer with a vnode.
2357 bgetvp(struct vnode *vp, struct buf *bp)
2362 ASSERT_BO_WLOCKED(bo);
2363 VNASSERT(bp->b_vp == NULL, bp->b_vp, ("bgetvp: not free"));
2365 CTR3(KTR_BUF, "bgetvp(%p) vp %p flags %X", bp, vp, bp->b_flags);
2366 VNASSERT((bp->b_xflags & (BX_VNDIRTY|BX_VNCLEAN)) == 0, vp,
2367 ("bgetvp: bp already attached! %p", bp));
2373 * Insert onto list for new vnode.
2375 buf_vlist_add(bp, bo, BX_VNCLEAN);
2379 * Disassociate a buffer from a vnode.
2382 brelvp(struct buf *bp)
2387 CTR3(KTR_BUF, "brelvp(%p) vp %p flags %X", bp, bp->b_vp, bp->b_flags);
2388 KASSERT(bp->b_vp != NULL, ("brelvp: NULL"));
2391 * Delete from old vnode list, if on one.
2393 vp = bp->b_vp; /* XXX */
2396 buf_vlist_remove(bp);
2397 if ((bo->bo_flag & BO_ONWORKLST) && bo->bo_dirty.bv_cnt == 0) {
2398 bo->bo_flag &= ~BO_ONWORKLST;
2399 mtx_lock(&sync_mtx);
2400 LIST_REMOVE(bo, bo_synclist);
2401 syncer_worklist_len--;
2402 mtx_unlock(&sync_mtx);
2405 bp->b_bufobj = NULL;
2411 * Add an item to the syncer work queue.
2414 vn_syncer_add_to_worklist(struct bufobj *bo, int delay)
2418 ASSERT_BO_WLOCKED(bo);
2420 mtx_lock(&sync_mtx);
2421 if (bo->bo_flag & BO_ONWORKLST)
2422 LIST_REMOVE(bo, bo_synclist);
2424 bo->bo_flag |= BO_ONWORKLST;
2425 syncer_worklist_len++;
2428 if (delay > syncer_maxdelay - 2)
2429 delay = syncer_maxdelay - 2;
2430 slot = (syncer_delayno + delay) & syncer_mask;
2432 LIST_INSERT_HEAD(&syncer_workitem_pending[slot], bo, bo_synclist);
2433 mtx_unlock(&sync_mtx);
2437 sysctl_vfs_worklist_len(SYSCTL_HANDLER_ARGS)
2441 mtx_lock(&sync_mtx);
2442 len = syncer_worklist_len - sync_vnode_count;
2443 mtx_unlock(&sync_mtx);
2444 error = SYSCTL_OUT(req, &len, sizeof(len));
2448 SYSCTL_PROC(_vfs, OID_AUTO, worklist_len,
2449 CTLTYPE_INT | CTLFLAG_MPSAFE| CTLFLAG_RD, NULL, 0,
2450 sysctl_vfs_worklist_len, "I", "Syncer thread worklist length");
2452 static struct proc *updateproc;
2453 static void sched_sync(void);
2454 static struct kproc_desc up_kp = {
2459 SYSINIT(syncer, SI_SUB_KTHREAD_UPDATE, SI_ORDER_FIRST, kproc_start, &up_kp);
2462 sync_vnode(struct synclist *slp, struct bufobj **bo, struct thread *td)
2467 *bo = LIST_FIRST(slp);
2471 if (VOP_ISLOCKED(vp) != 0 || VI_TRYLOCK(vp) == 0)
2474 * We use vhold in case the vnode does not
2475 * successfully sync. vhold prevents the vnode from
2476 * going away when we unlock the sync_mtx so that
2477 * we can acquire the vnode interlock.
2480 mtx_unlock(&sync_mtx);
2482 if (vn_start_write(vp, &mp, V_NOWAIT) != 0) {
2484 mtx_lock(&sync_mtx);
2485 return (*bo == LIST_FIRST(slp));
2487 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
2488 (void) VOP_FSYNC(vp, MNT_LAZY, td);
2490 vn_finished_write(mp);
2492 if (((*bo)->bo_flag & BO_ONWORKLST) != 0) {
2494 * Put us back on the worklist. The worklist
2495 * routine will remove us from our current
2496 * position and then add us back in at a later
2499 vn_syncer_add_to_worklist(*bo, syncdelay);
2503 mtx_lock(&sync_mtx);
2507 static int first_printf = 1;
2510 * System filesystem synchronizer daemon.
2515 struct synclist *next, *slp;
2518 struct thread *td = curthread;
2520 int net_worklist_len;
2521 int syncer_final_iter;
2525 syncer_final_iter = 0;
2526 syncer_state = SYNCER_RUNNING;
2527 starttime = time_uptime;
2528 td->td_pflags |= TDP_NORUNNINGBUF;
2530 EVENTHANDLER_REGISTER(shutdown_pre_sync, syncer_shutdown, td->td_proc,
2533 mtx_lock(&sync_mtx);
2535 if (syncer_state == SYNCER_FINAL_DELAY &&
2536 syncer_final_iter == 0) {
2537 mtx_unlock(&sync_mtx);
2538 kproc_suspend_check(td->td_proc);
2539 mtx_lock(&sync_mtx);
2541 net_worklist_len = syncer_worklist_len - sync_vnode_count;
2542 if (syncer_state != SYNCER_RUNNING &&
2543 starttime != time_uptime) {
2545 printf("\nSyncing disks, vnodes remaining... ");
2548 printf("%d ", net_worklist_len);
2550 starttime = time_uptime;
2553 * Push files whose dirty time has expired. Be careful
2554 * of interrupt race on slp queue.
2556 * Skip over empty worklist slots when shutting down.
2559 slp = &syncer_workitem_pending[syncer_delayno];
2560 syncer_delayno += 1;
2561 if (syncer_delayno == syncer_maxdelay)
2563 next = &syncer_workitem_pending[syncer_delayno];
2565 * If the worklist has wrapped since the
2566 * it was emptied of all but syncer vnodes,
2567 * switch to the FINAL_DELAY state and run
2568 * for one more second.
2570 if (syncer_state == SYNCER_SHUTTING_DOWN &&
2571 net_worklist_len == 0 &&
2572 last_work_seen == syncer_delayno) {
2573 syncer_state = SYNCER_FINAL_DELAY;
2574 syncer_final_iter = SYNCER_SHUTDOWN_SPEEDUP;
2576 } while (syncer_state != SYNCER_RUNNING && LIST_EMPTY(slp) &&
2577 syncer_worklist_len > 0);
2580 * Keep track of the last time there was anything
2581 * on the worklist other than syncer vnodes.
2582 * Return to the SHUTTING_DOWN state if any
2585 if (net_worklist_len > 0 || syncer_state == SYNCER_RUNNING)
2586 last_work_seen = syncer_delayno;
2587 if (net_worklist_len > 0 && syncer_state == SYNCER_FINAL_DELAY)
2588 syncer_state = SYNCER_SHUTTING_DOWN;
2589 while (!LIST_EMPTY(slp)) {
2590 error = sync_vnode(slp, &bo, td);
2592 LIST_REMOVE(bo, bo_synclist);
2593 LIST_INSERT_HEAD(next, bo, bo_synclist);
2597 if (first_printf == 0) {
2599 * Drop the sync mutex, because some watchdog
2600 * drivers need to sleep while patting
2602 mtx_unlock(&sync_mtx);
2603 wdog_kern_pat(WD_LASTVAL);
2604 mtx_lock(&sync_mtx);
2608 if (syncer_state == SYNCER_FINAL_DELAY && syncer_final_iter > 0)
2609 syncer_final_iter--;
2611 * The variable rushjob allows the kernel to speed up the
2612 * processing of the filesystem syncer process. A rushjob
2613 * value of N tells the filesystem syncer to process the next
2614 * N seconds worth of work on its queue ASAP. Currently rushjob
2615 * is used by the soft update code to speed up the filesystem
2616 * syncer process when the incore state is getting so far
2617 * ahead of the disk that the kernel memory pool is being
2618 * threatened with exhaustion.
2625 * Just sleep for a short period of time between
2626 * iterations when shutting down to allow some I/O
2629 * If it has taken us less than a second to process the
2630 * current work, then wait. Otherwise start right over
2631 * again. We can still lose time if any single round
2632 * takes more than two seconds, but it does not really
2633 * matter as we are just trying to generally pace the
2634 * filesystem activity.
2636 if (syncer_state != SYNCER_RUNNING ||
2637 time_uptime == starttime) {
2639 sched_prio(td, PPAUSE);
2642 if (syncer_state != SYNCER_RUNNING)
2643 cv_timedwait(&sync_wakeup, &sync_mtx,
2644 hz / SYNCER_SHUTDOWN_SPEEDUP);
2645 else if (time_uptime == starttime)
2646 cv_timedwait(&sync_wakeup, &sync_mtx, hz);
2651 * Request the syncer daemon to speed up its work.
2652 * We never push it to speed up more than half of its
2653 * normal turn time, otherwise it could take over the cpu.
2656 speedup_syncer(void)
2660 mtx_lock(&sync_mtx);
2661 if (rushjob < syncdelay / 2) {
2663 stat_rush_requests += 1;
2666 mtx_unlock(&sync_mtx);
2667 cv_broadcast(&sync_wakeup);
2672 * Tell the syncer to speed up its work and run though its work
2673 * list several times, then tell it to shut down.
2676 syncer_shutdown(void *arg, int howto)
2679 if (howto & RB_NOSYNC)
2681 mtx_lock(&sync_mtx);
2682 syncer_state = SYNCER_SHUTTING_DOWN;
2684 mtx_unlock(&sync_mtx);
2685 cv_broadcast(&sync_wakeup);
2686 kproc_shutdown(arg, howto);
2690 syncer_suspend(void)
2693 syncer_shutdown(updateproc, 0);
2700 mtx_lock(&sync_mtx);
2702 syncer_state = SYNCER_RUNNING;
2703 mtx_unlock(&sync_mtx);
2704 cv_broadcast(&sync_wakeup);
2705 kproc_resume(updateproc);
2709 * Move the buffer between the clean and dirty lists of its vnode.
2712 reassignbuf(struct buf *bp)
2724 KASSERT((bp->b_flags & B_PAGING) == 0,
2725 ("%s: cannot reassign paging buffer %p", __func__, bp));
2727 CTR3(KTR_BUF, "reassignbuf(%p) vp %p flags %X",
2728 bp, bp->b_vp, bp->b_flags);
2731 buf_vlist_remove(bp);
2734 * If dirty, put on list of dirty buffers; otherwise insert onto list
2737 if (bp->b_flags & B_DELWRI) {
2738 if ((bo->bo_flag & BO_ONWORKLST) == 0) {
2739 switch (vp->v_type) {
2749 vn_syncer_add_to_worklist(bo, delay);
2751 buf_vlist_add(bp, bo, BX_VNDIRTY);
2753 buf_vlist_add(bp, bo, BX_VNCLEAN);
2755 if ((bo->bo_flag & BO_ONWORKLST) && bo->bo_dirty.bv_cnt == 0) {
2756 mtx_lock(&sync_mtx);
2757 LIST_REMOVE(bo, bo_synclist);
2758 syncer_worklist_len--;
2759 mtx_unlock(&sync_mtx);
2760 bo->bo_flag &= ~BO_ONWORKLST;
2765 bp = TAILQ_FIRST(&bv->bv_hd);
2766 KASSERT(bp == NULL || bp->b_bufobj == bo,
2767 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo));
2768 bp = TAILQ_LAST(&bv->bv_hd, buflists);
2769 KASSERT(bp == NULL || bp->b_bufobj == bo,
2770 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo));
2772 bp = TAILQ_FIRST(&bv->bv_hd);
2773 KASSERT(bp == NULL || bp->b_bufobj == bo,
2774 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo));
2775 bp = TAILQ_LAST(&bv->bv_hd, buflists);
2776 KASSERT(bp == NULL || bp->b_bufobj == bo,
2777 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo));
2783 v_init_counters(struct vnode *vp)
2786 VNASSERT(vp->v_type == VNON && vp->v_data == NULL && vp->v_iflag == 0,
2787 vp, ("%s called for an initialized vnode", __FUNCTION__));
2788 ASSERT_VI_UNLOCKED(vp, __FUNCTION__);
2790 refcount_init(&vp->v_holdcnt, 1);
2791 refcount_init(&vp->v_usecount, 1);
2795 * Grab a particular vnode from the free list, increment its
2796 * reference count and lock it. VIRF_DOOMED is set if the vnode
2797 * is being destroyed. Only callers who specify LK_RETRY will
2798 * see doomed vnodes. If inactive processing was delayed in
2799 * vput try to do it here.
2801 * usecount is manipulated using atomics without holding any locks.
2803 * holdcnt can be manipulated using atomics without holding any locks,
2804 * except when transitioning 1<->0, in which case the interlock is held.
2806 * Consumers which don't guarantee liveness of the vnode can use SMR to
2807 * try to get a reference. Note this operation can fail since the vnode
2808 * may be awaiting getting freed by the time they get to it.
2811 vget_prep_smr(struct vnode *vp)
2815 VFS_SMR_ASSERT_ENTERED();
2817 if (refcount_acquire_if_not_zero(&vp->v_usecount)) {
2829 vget_prep(struct vnode *vp)
2833 if (refcount_acquire_if_not_zero(&vp->v_usecount)) {
2843 vget_abort(struct vnode *vp, enum vgetstate vs)
2854 __assert_unreachable();
2859 vget(struct vnode *vp, int flags)
2864 return (vget_finish(vp, flags, vs));
2868 vget_finish(struct vnode *vp, int flags, enum vgetstate vs)
2872 if ((flags & LK_INTERLOCK) != 0)
2873 ASSERT_VI_LOCKED(vp, __func__);
2875 ASSERT_VI_UNLOCKED(vp, __func__);
2876 VNPASS(vs == VGET_HOLDCNT || vs == VGET_USECOUNT, vp);
2877 VNPASS(vp->v_holdcnt > 0, vp);
2878 VNPASS(vs == VGET_HOLDCNT || vp->v_usecount > 0, vp);
2880 error = vn_lock(vp, flags);
2881 if (__predict_false(error != 0)) {
2883 CTR2(KTR_VFS, "%s: impossible to lock vnode %p", __func__,
2888 vget_finish_ref(vp, vs);
2893 vget_finish_ref(struct vnode *vp, enum vgetstate vs)
2897 VNPASS(vs == VGET_HOLDCNT || vs == VGET_USECOUNT, vp);
2898 VNPASS(vp->v_holdcnt > 0, vp);
2899 VNPASS(vs == VGET_HOLDCNT || vp->v_usecount > 0, vp);
2901 if (vs == VGET_USECOUNT)
2905 * We hold the vnode. If the usecount is 0 it will be utilized to keep
2906 * the vnode around. Otherwise someone else lended their hold count and
2907 * we have to drop ours.
2909 old = atomic_fetchadd_int(&vp->v_usecount, 1);
2910 VNASSERT(old >= 0, vp, ("%s: wrong use count %d", __func__, old));
2913 old = atomic_fetchadd_int(&vp->v_holdcnt, -1);
2914 VNASSERT(old > 1, vp, ("%s: wrong hold count %d", __func__, old));
2916 refcount_release(&vp->v_holdcnt);
2922 vref(struct vnode *vp)
2926 CTR2(KTR_VFS, "%s: vp %p", __func__, vp);
2928 vget_finish_ref(vp, vs);
2932 vrefact(struct vnode *vp)
2935 CTR2(KTR_VFS, "%s: vp %p", __func__, vp);
2937 int old = atomic_fetchadd_int(&vp->v_usecount, 1);
2938 VNASSERT(old > 0, vp, ("%s: wrong use count %d", __func__, old));
2940 refcount_acquire(&vp->v_usecount);
2945 vlazy(struct vnode *vp)
2949 VNASSERT(vp->v_holdcnt > 0, vp, ("%s: vnode not held", __func__));
2951 if ((vp->v_mflag & VMP_LAZYLIST) != 0)
2954 * We may get here for inactive routines after the vnode got doomed.
2956 if (VN_IS_DOOMED(vp))
2959 mtx_lock(&mp->mnt_listmtx);
2960 if ((vp->v_mflag & VMP_LAZYLIST) == 0) {
2961 vp->v_mflag |= VMP_LAZYLIST;
2962 TAILQ_INSERT_TAIL(&mp->mnt_lazyvnodelist, vp, v_lazylist);
2963 mp->mnt_lazyvnodelistsize++;
2965 mtx_unlock(&mp->mnt_listmtx);
2969 * This routine is only meant to be called from vgonel prior to dooming
2973 vunlazy_gone(struct vnode *vp)
2977 ASSERT_VOP_ELOCKED(vp, __func__);
2978 ASSERT_VI_LOCKED(vp, __func__);
2979 VNPASS(!VN_IS_DOOMED(vp), vp);
2981 if (vp->v_mflag & VMP_LAZYLIST) {
2983 mtx_lock(&mp->mnt_listmtx);
2984 VNPASS(vp->v_mflag & VMP_LAZYLIST, vp);
2985 vp->v_mflag &= ~VMP_LAZYLIST;
2986 TAILQ_REMOVE(&mp->mnt_lazyvnodelist, vp, v_lazylist);
2987 mp->mnt_lazyvnodelistsize--;
2988 mtx_unlock(&mp->mnt_listmtx);
2993 vdefer_inactive(struct vnode *vp)
2996 ASSERT_VI_LOCKED(vp, __func__);
2997 VNASSERT(vp->v_holdcnt > 0, vp,
2998 ("%s: vnode without hold count", __func__));
2999 if (VN_IS_DOOMED(vp)) {
3003 if (vp->v_iflag & VI_DEFINACT) {
3004 VNASSERT(vp->v_holdcnt > 1, vp, ("lost hold count"));
3008 if (vp->v_usecount > 0) {
3009 vp->v_iflag &= ~VI_OWEINACT;
3014 vp->v_iflag |= VI_DEFINACT;
3016 counter_u64_add(deferred_inact, 1);
3020 vdefer_inactive_unlocked(struct vnode *vp)
3024 if ((vp->v_iflag & VI_OWEINACT) == 0) {
3028 vdefer_inactive(vp);
3031 enum vput_op { VRELE, VPUT, VUNREF };
3034 * Handle ->v_usecount transitioning to 0.
3036 * By releasing the last usecount we take ownership of the hold count which
3037 * provides liveness of the vnode, meaning we have to vdrop.
3039 * For all vnodes we may need to perform inactive processing. It requires an
3040 * exclusive lock on the vnode, while it is legal to call here with only a
3041 * shared lock (or no locks). If locking the vnode in an expected manner fails,
3042 * inactive processing gets deferred to the syncer.
3044 * XXX Some filesystems pass in an exclusively locked vnode and strongly depend
3045 * on the lock being held all the way until VOP_INACTIVE. This in particular
3046 * happens with UFS which adds half-constructed vnodes to the hash, where they
3047 * can be found by other code.
3050 vput_final(struct vnode *vp, enum vput_op func)
3055 CTR2(KTR_VFS, "%s: vp %p", __func__, vp);
3056 VNPASS(vp->v_holdcnt > 0, vp);
3061 * By the time we got here someone else might have transitioned
3062 * the count back to > 0.
3064 if (vp->v_usecount > 0)
3068 * If the vnode is doomed vgone already performed inactive processing
3071 if (VN_IS_DOOMED(vp))
3074 if (__predict_true(VOP_NEED_INACTIVE(vp) == 0))
3077 if (vp->v_iflag & VI_DOINGINACT)
3081 * Locking operations here will drop the interlock and possibly the
3082 * vnode lock, opening a window where the vnode can get doomed all the
3083 * while ->v_usecount is 0. Set VI_OWEINACT to let vgone know to
3086 vp->v_iflag |= VI_OWEINACT;
3087 want_unlock = false;
3091 switch (VOP_ISLOCKED(vp)) {
3097 error = vn_lock(vp, LK_EXCLUSIVE | LK_INTERLOCK);
3102 * The lock has at least one sharer, but we have no way
3103 * to conclude whether this is us. Play it safe and
3112 if (VOP_ISLOCKED(vp) != LK_EXCLUSIVE) {
3113 error = VOP_LOCK(vp, LK_UPGRADE | LK_INTERLOCK |
3119 if (VOP_ISLOCKED(vp) != LK_EXCLUSIVE) {
3120 error = VOP_LOCK(vp, LK_TRYUPGRADE | LK_INTERLOCK);
3131 vdefer_inactive(vp);
3141 * Decrement ->v_usecount for a vnode.
3143 * Releasing the last use count requires additional processing, see vput_final
3144 * above for details.
3146 * Comment above each variant denotes lock state on entry and exit.
3151 * out: same as passed in
3154 vrele(struct vnode *vp)
3157 ASSERT_VI_UNLOCKED(vp, __func__);
3158 if (!refcount_release(&vp->v_usecount))
3160 vput_final(vp, VRELE);
3168 vput(struct vnode *vp)
3171 ASSERT_VOP_LOCKED(vp, __func__);
3172 ASSERT_VI_UNLOCKED(vp, __func__);
3173 if (!refcount_release(&vp->v_usecount)) {
3177 vput_final(vp, VPUT);
3185 vunref(struct vnode *vp)
3188 ASSERT_VOP_LOCKED(vp, __func__);
3189 ASSERT_VI_UNLOCKED(vp, __func__);
3190 if (!refcount_release(&vp->v_usecount))
3192 vput_final(vp, VUNREF);
3196 vhold(struct vnode *vp)
3201 CTR2(KTR_VFS, "%s: vp %p", __func__, vp);
3202 old = atomic_fetchadd_int(&vp->v_holdcnt, 1);
3203 VNASSERT(old >= 0 && (old & VHOLD_ALL_FLAGS) == 0, vp,
3204 ("%s: wrong hold count %d", __func__, old));
3214 vholdl(struct vnode *vp)
3217 ASSERT_VI_LOCKED(vp, __func__);
3218 CTR2(KTR_VFS, "%s: vp %p", __func__, vp);
3223 vholdnz(struct vnode *vp)
3226 CTR2(KTR_VFS, "%s: vp %p", __func__, vp);
3228 int old = atomic_fetchadd_int(&vp->v_holdcnt, 1);
3229 VNASSERT(old > 0 && (old & VHOLD_ALL_FLAGS) == 0, vp,
3230 ("%s: wrong hold count %d", __func__, old));
3232 atomic_add_int(&vp->v_holdcnt, 1);
3237 * Grab a hold count unless the vnode is freed.
3239 * Only use this routine if vfs smr is the only protection you have against
3240 * freeing the vnode.
3242 * The code loops trying to add a hold count as long as the VHOLD_NO_SMR flag
3243 * is not set. After the flag is set the vnode becomes immutable to anyone but
3244 * the thread which managed to set the flag.
3246 * It may be tempting to replace the loop with:
3247 * count = atomic_fetchadd_int(&vp->v_holdcnt, 1);
3248 * if (count & VHOLD_NO_SMR) {
3249 * backpedal and error out;
3252 * However, while this is more performant, it hinders debugging by eliminating
3253 * the previously mentioned invariant.
3256 vhold_smr(struct vnode *vp)
3260 VFS_SMR_ASSERT_ENTERED();
3262 count = atomic_load_int(&vp->v_holdcnt);
3264 if (count & VHOLD_NO_SMR) {
3265 VNASSERT((count & ~VHOLD_NO_SMR) == 0, vp,
3266 ("non-zero hold count with flags %d\n", count));
3270 VNASSERT(count >= 0, vp, ("invalid hold count %d\n", count));
3271 if (atomic_fcmpset_int(&vp->v_holdcnt, &count, count + 1))
3276 static void __noinline
3277 vdbatch_process(struct vdbatch *vd)
3282 mtx_assert(&vd->lock, MA_OWNED);
3283 MPASS(curthread->td_pinned > 0);
3284 MPASS(vd->index == VDBATCH_SIZE);
3286 mtx_lock(&vnode_list_mtx);
3288 freevnodes += vd->freevnodes;
3289 for (i = 0; i < VDBATCH_SIZE; i++) {
3291 TAILQ_REMOVE(&vnode_list, vp, v_vnodelist);
3292 TAILQ_INSERT_TAIL(&vnode_list, vp, v_vnodelist);
3293 MPASS(vp->v_dbatchcpu != NOCPU);
3294 vp->v_dbatchcpu = NOCPU;
3296 mtx_unlock(&vnode_list_mtx);
3298 bzero(vd->tab, sizeof(vd->tab));
3304 vdbatch_enqueue(struct vnode *vp)
3308 ASSERT_VI_LOCKED(vp, __func__);
3309 VNASSERT(!VN_IS_DOOMED(vp), vp,
3310 ("%s: deferring requeue of a doomed vnode", __func__));
3315 if (vp->v_dbatchcpu != NOCPU) {
3323 mtx_lock(&vd->lock);
3324 MPASS(vd->index < VDBATCH_SIZE);
3325 MPASS(vd->tab[vd->index] == NULL);
3327 * A hack: we depend on being pinned so that we know what to put in
3330 vp->v_dbatchcpu = curcpu;
3331 vd->tab[vd->index] = vp;
3334 if (vd->index == VDBATCH_SIZE)
3335 vdbatch_process(vd);
3336 mtx_unlock(&vd->lock);
3341 * This routine must only be called for vnodes which are about to be
3342 * deallocated. Supporting dequeue for arbitrary vndoes would require
3343 * validating that the locked batch matches.
3346 vdbatch_dequeue(struct vnode *vp)
3352 VNASSERT(vp->v_type == VBAD || vp->v_type == VNON, vp,
3353 ("%s: called for a used vnode\n", __func__));
3355 cpu = vp->v_dbatchcpu;
3359 vd = DPCPU_ID_PTR(cpu, vd);
3360 mtx_lock(&vd->lock);
3361 for (i = 0; i < vd->index; i++) {
3362 if (vd->tab[i] != vp)
3364 vp->v_dbatchcpu = NOCPU;
3366 vd->tab[i] = vd->tab[vd->index];
3367 vd->tab[vd->index] = NULL;
3370 mtx_unlock(&vd->lock);
3372 * Either we dequeued the vnode above or the target CPU beat us to it.
3374 MPASS(vp->v_dbatchcpu == NOCPU);
3378 * Drop the hold count of the vnode. If this is the last reference to
3379 * the vnode we place it on the free list unless it has been vgone'd
3380 * (marked VIRF_DOOMED) in which case we will free it.
3382 * Because the vnode vm object keeps a hold reference on the vnode if
3383 * there is at least one resident non-cached page, the vnode cannot
3384 * leave the active list without the page cleanup done.
3387 vdrop_deactivate(struct vnode *vp)
3391 ASSERT_VI_LOCKED(vp, __func__);
3393 * Mark a vnode as free: remove it from its active list
3394 * and put it up for recycling on the freelist.
3396 VNASSERT(!VN_IS_DOOMED(vp), vp,
3397 ("vdrop: returning doomed vnode"));
3398 VNASSERT(vp->v_op != NULL, vp,
3399 ("vdrop: vnode already reclaimed."));
3400 VNASSERT((vp->v_iflag & VI_OWEINACT) == 0, vp,
3401 ("vnode with VI_OWEINACT set"));
3402 VNASSERT((vp->v_iflag & VI_DEFINACT) == 0, vp,
3403 ("vnode with VI_DEFINACT set"));
3404 if (vp->v_mflag & VMP_LAZYLIST) {
3406 mtx_lock(&mp->mnt_listmtx);
3407 VNASSERT(vp->v_mflag & VMP_LAZYLIST, vp, ("lost VMP_LAZYLIST"));
3409 * Don't remove the vnode from the lazy list if another thread
3410 * has increased the hold count. It may have re-enqueued the
3411 * vnode to the lazy list and is now responsible for its
3414 if (vp->v_holdcnt == 0) {
3415 vp->v_mflag &= ~VMP_LAZYLIST;
3416 TAILQ_REMOVE(&mp->mnt_lazyvnodelist, vp, v_lazylist);
3417 mp->mnt_lazyvnodelistsize--;
3419 mtx_unlock(&mp->mnt_listmtx);
3421 vdbatch_enqueue(vp);
3425 vdrop(struct vnode *vp)
3428 ASSERT_VI_UNLOCKED(vp, __func__);
3429 CTR2(KTR_VFS, "%s: vp %p", __func__, vp);
3430 if (refcount_release_if_not_last(&vp->v_holdcnt))
3437 vdropl(struct vnode *vp)
3440 ASSERT_VI_LOCKED(vp, __func__);
3441 CTR2(KTR_VFS, "%s: vp %p", __func__, vp);
3442 if (!refcount_release(&vp->v_holdcnt)) {
3446 if (!VN_IS_DOOMED(vp)) {
3447 vdrop_deactivate(vp);
3449 * Also unlocks the interlock. We can't assert on it as we
3450 * released our hold and by now the vnode might have been
3456 * Set the VHOLD_NO_SMR flag.
3458 * We may be racing against vhold_smr. If they win we can just pretend
3459 * we never got this far, they will vdrop later.
3461 if (!atomic_cmpset_int(&vp->v_holdcnt, 0, VHOLD_NO_SMR)) {
3464 * We lost the aforementioned race. Any subsequent access is
3465 * invalid as they might have managed to vdropl on their own.
3473 * Call VOP_INACTIVE on the vnode and manage the DOINGINACT and OWEINACT
3474 * flags. DOINGINACT prevents us from recursing in calls to vinactive.
3477 vinactivef(struct vnode *vp)
3479 struct vm_object *obj;
3481 ASSERT_VOP_ELOCKED(vp, "vinactive");
3482 ASSERT_VI_LOCKED(vp, "vinactive");
3483 VNASSERT((vp->v_iflag & VI_DOINGINACT) == 0, vp,
3484 ("vinactive: recursed on VI_DOINGINACT"));
3485 CTR2(KTR_VFS, "%s: vp %p", __func__, vp);
3486 vp->v_iflag |= VI_DOINGINACT;
3487 vp->v_iflag &= ~VI_OWEINACT;
3490 * Before moving off the active list, we must be sure that any
3491 * modified pages are converted into the vnode's dirty
3492 * buffers, since these will no longer be checked once the
3493 * vnode is on the inactive list.
3495 * The write-out of the dirty pages is asynchronous. At the
3496 * point that VOP_INACTIVE() is called, there could still be
3497 * pending I/O and dirty pages in the object.
3499 if ((obj = vp->v_object) != NULL && (vp->v_vflag & VV_NOSYNC) == 0 &&
3500 vm_object_mightbedirty(obj)) {
3501 VM_OBJECT_WLOCK(obj);
3502 vm_object_page_clean(obj, 0, 0, 0);
3503 VM_OBJECT_WUNLOCK(obj);
3505 VOP_INACTIVE(vp, curthread);
3507 VNASSERT(vp->v_iflag & VI_DOINGINACT, vp,
3508 ("vinactive: lost VI_DOINGINACT"));
3509 vp->v_iflag &= ~VI_DOINGINACT;
3513 vinactive(struct vnode *vp)
3516 ASSERT_VOP_ELOCKED(vp, "vinactive");
3517 ASSERT_VI_LOCKED(vp, "vinactive");
3518 CTR2(KTR_VFS, "%s: vp %p", __func__, vp);
3520 if ((vp->v_iflag & VI_OWEINACT) == 0)
3522 if (vp->v_iflag & VI_DOINGINACT)
3524 if (vp->v_usecount > 0) {
3525 vp->v_iflag &= ~VI_OWEINACT;
3532 * Remove any vnodes in the vnode table belonging to mount point mp.
3534 * If FORCECLOSE is not specified, there should not be any active ones,
3535 * return error if any are found (nb: this is a user error, not a
3536 * system error). If FORCECLOSE is specified, detach any active vnodes
3539 * If WRITECLOSE is set, only flush out regular file vnodes open for
3542 * SKIPSYSTEM causes any vnodes marked VV_SYSTEM to be skipped.
3544 * `rootrefs' specifies the base reference count for the root vnode
3545 * of this filesystem. The root vnode is considered busy if its
3546 * v_usecount exceeds this value. On a successful return, vflush(, td)
3547 * will call vrele() on the root vnode exactly rootrefs times.
3548 * If the SKIPSYSTEM or WRITECLOSE flags are specified, rootrefs must
3552 static int busyprt = 0; /* print out busy vnodes */
3553 SYSCTL_INT(_debug, OID_AUTO, busyprt, CTLFLAG_RW, &busyprt, 0, "Print out busy vnodes");
3557 vflush(struct mount *mp, int rootrefs, int flags, struct thread *td)
3559 struct vnode *vp, *mvp, *rootvp = NULL;
3561 int busy = 0, error;
3563 CTR4(KTR_VFS, "%s: mp %p with rootrefs %d and flags %d", __func__, mp,
3566 KASSERT((flags & (SKIPSYSTEM | WRITECLOSE)) == 0,
3567 ("vflush: bad args"));
3569 * Get the filesystem root vnode. We can vput() it
3570 * immediately, since with rootrefs > 0, it won't go away.
3572 if ((error = VFS_ROOT(mp, LK_EXCLUSIVE, &rootvp)) != 0) {
3573 CTR2(KTR_VFS, "%s: vfs_root lookup failed with %d",
3580 MNT_VNODE_FOREACH_ALL(vp, mp, mvp) {
3582 error = vn_lock(vp, LK_INTERLOCK | LK_EXCLUSIVE);
3585 MNT_VNODE_FOREACH_ALL_ABORT(mp, mvp);
3589 * Skip over a vnodes marked VV_SYSTEM.
3591 if ((flags & SKIPSYSTEM) && (vp->v_vflag & VV_SYSTEM)) {
3597 * If WRITECLOSE is set, flush out unlinked but still open
3598 * files (even if open only for reading) and regular file
3599 * vnodes open for writing.
3601 if (flags & WRITECLOSE) {
3602 if (vp->v_object != NULL) {
3603 VM_OBJECT_WLOCK(vp->v_object);
3604 vm_object_page_clean(vp->v_object, 0, 0, 0);
3605 VM_OBJECT_WUNLOCK(vp->v_object);
3607 error = VOP_FSYNC(vp, MNT_WAIT, td);
3611 MNT_VNODE_FOREACH_ALL_ABORT(mp, mvp);
3614 error = VOP_GETATTR(vp, &vattr, td->td_ucred);
3617 if ((vp->v_type == VNON ||
3618 (error == 0 && vattr.va_nlink > 0)) &&
3619 (vp->v_writecount <= 0 || vp->v_type != VREG)) {
3627 * With v_usecount == 0, all we need to do is clear out the
3628 * vnode data structures and we are done.
3630 * If FORCECLOSE is set, forcibly close the vnode.
3632 if (vp->v_usecount == 0 || (flags & FORCECLOSE)) {
3638 vn_printf(vp, "vflush: busy vnode ");
3644 if (rootrefs > 0 && (flags & FORCECLOSE) == 0) {
3646 * If just the root vnode is busy, and if its refcount
3647 * is equal to `rootrefs', then go ahead and kill it.
3650 KASSERT(busy > 0, ("vflush: not busy"));
3651 VNASSERT(rootvp->v_usecount >= rootrefs, rootvp,
3652 ("vflush: usecount %d < rootrefs %d",
3653 rootvp->v_usecount, rootrefs));
3654 if (busy == 1 && rootvp->v_usecount == rootrefs) {
3655 VOP_LOCK(rootvp, LK_EXCLUSIVE|LK_INTERLOCK);
3663 CTR2(KTR_VFS, "%s: failing as %d vnodes are busy", __func__,
3667 for (; rootrefs > 0; rootrefs--)
3673 * Recycle an unused vnode to the front of the free list.
3676 vrecycle(struct vnode *vp)
3681 recycled = vrecyclel(vp);
3687 * vrecycle, with the vp interlock held.
3690 vrecyclel(struct vnode *vp)
3694 ASSERT_VOP_ELOCKED(vp, __func__);
3695 ASSERT_VI_LOCKED(vp, __func__);
3696 CTR2(KTR_VFS, "%s: vp %p", __func__, vp);
3698 if (vp->v_usecount == 0) {
3706 * Eliminate all activity associated with a vnode
3707 * in preparation for reuse.
3710 vgone(struct vnode *vp)
3718 notify_lowervp_vfs_dummy(struct mount *mp __unused,
3719 struct vnode *lowervp __unused)
3724 * Notify upper mounts about reclaimed or unlinked vnode.
3727 vfs_notify_upper(struct vnode *vp, int event)
3729 static struct vfsops vgonel_vfsops = {
3730 .vfs_reclaim_lowervp = notify_lowervp_vfs_dummy,
3731 .vfs_unlink_lowervp = notify_lowervp_vfs_dummy,
3733 struct mount *mp, *ump, *mmp;
3738 if (TAILQ_EMPTY(&mp->mnt_uppers))
3741 mmp = malloc(sizeof(struct mount), M_TEMP, M_WAITOK | M_ZERO);
3742 mmp->mnt_op = &vgonel_vfsops;
3743 mmp->mnt_kern_flag |= MNTK_MARKER;
3745 mp->mnt_kern_flag |= MNTK_VGONE_UPPER;
3746 for (ump = TAILQ_FIRST(&mp->mnt_uppers); ump != NULL;) {
3747 if ((ump->mnt_kern_flag & MNTK_MARKER) != 0) {
3748 ump = TAILQ_NEXT(ump, mnt_upper_link);
3751 TAILQ_INSERT_AFTER(&mp->mnt_uppers, ump, mmp, mnt_upper_link);
3754 case VFS_NOTIFY_UPPER_RECLAIM:
3755 VFS_RECLAIM_LOWERVP(ump, vp);
3757 case VFS_NOTIFY_UPPER_UNLINK:
3758 VFS_UNLINK_LOWERVP(ump, vp);
3761 KASSERT(0, ("invalid event %d", event));
3765 ump = TAILQ_NEXT(mmp, mnt_upper_link);
3766 TAILQ_REMOVE(&mp->mnt_uppers, mmp, mnt_upper_link);
3769 mp->mnt_kern_flag &= ~MNTK_VGONE_UPPER;
3770 if ((mp->mnt_kern_flag & MNTK_VGONE_WAITER) != 0) {
3771 mp->mnt_kern_flag &= ~MNTK_VGONE_WAITER;
3772 wakeup(&mp->mnt_uppers);
3778 * vgone, with the vp interlock held.
3781 vgonel(struct vnode *vp)
3786 bool active, oweinact;
3788 ASSERT_VOP_ELOCKED(vp, "vgonel");
3789 ASSERT_VI_LOCKED(vp, "vgonel");
3790 VNASSERT(vp->v_holdcnt, vp,
3791 ("vgonel: vp %p has no reference.", vp));
3792 CTR2(KTR_VFS, "%s: vp %p", __func__, vp);
3796 * Don't vgonel if we're already doomed.
3798 if (vp->v_irflag & VIRF_DOOMED)
3801 * Paired with freevnode.
3803 vn_seqc_write_begin_locked(vp);
3805 vp->v_irflag |= VIRF_DOOMED;
3808 * Check to see if the vnode is in use. If so, we have to call
3809 * VOP_CLOSE() and VOP_INACTIVE().
3811 active = vp->v_usecount > 0;
3812 oweinact = (vp->v_iflag & VI_OWEINACT) != 0;
3814 * If we need to do inactive VI_OWEINACT will be set.
3816 if (vp->v_iflag & VI_DEFINACT) {
3817 VNASSERT(vp->v_holdcnt > 1, vp, ("lost hold count"));
3818 vp->v_iflag &= ~VI_DEFINACT;
3821 VNASSERT(vp->v_holdcnt > 0, vp, ("vnode without hold count"));
3824 vfs_notify_upper(vp, VFS_NOTIFY_UPPER_RECLAIM);
3827 * If purging an active vnode, it must be closed and
3828 * deactivated before being reclaimed.
3831 VOP_CLOSE(vp, FNONBLOCK, NOCRED, td);
3832 if (oweinact || active) {
3837 if (vp->v_type == VSOCK)
3838 vfs_unp_reclaim(vp);
3841 * Clean out any buffers associated with the vnode.
3842 * If the flush fails, just toss the buffers.
3845 if (!TAILQ_EMPTY(&vp->v_bufobj.bo_dirty.bv_hd))
3846 (void) vn_start_secondary_write(vp, &mp, V_WAIT);
3847 if (vinvalbuf(vp, V_SAVE, 0, 0) != 0) {
3848 while (vinvalbuf(vp, 0, 0, 0) != 0)
3852 BO_LOCK(&vp->v_bufobj);
3853 KASSERT(TAILQ_EMPTY(&vp->v_bufobj.bo_dirty.bv_hd) &&
3854 vp->v_bufobj.bo_dirty.bv_cnt == 0 &&
3855 TAILQ_EMPTY(&vp->v_bufobj.bo_clean.bv_hd) &&
3856 vp->v_bufobj.bo_clean.bv_cnt == 0,
3857 ("vp %p bufobj not invalidated", vp));
3860 * For VMIO bufobj, BO_DEAD is set later, or in
3861 * vm_object_terminate() after the object's page queue is
3864 object = vp->v_bufobj.bo_object;
3866 vp->v_bufobj.bo_flag |= BO_DEAD;
3867 BO_UNLOCK(&vp->v_bufobj);
3870 * Handle the VM part. Tmpfs handles v_object on its own (the
3871 * OBJT_VNODE check). Nullfs or other bypassing filesystems
3872 * should not touch the object borrowed from the lower vnode
3873 * (the handle check).
3875 if (object != NULL && object->type == OBJT_VNODE &&
3876 object->handle == vp)
3877 vnode_destroy_vobject(vp);
3880 * Reclaim the vnode.
3882 if (VOP_RECLAIM(vp))
3883 panic("vgone: cannot reclaim");
3885 vn_finished_secondary_write(mp);
3886 VNASSERT(vp->v_object == NULL, vp,
3887 ("vop_reclaim left v_object vp=%p", vp));
3889 * Clear the advisory locks and wake up waiting threads.
3891 (void)VOP_ADVLOCKPURGE(vp);
3894 * Delete from old mount point vnode list.
3897 cache_purge_vgone(vp);
3899 * Done with purge, reset to the standard lock and invalidate
3903 vp->v_vnlock = &vp->v_lock;
3904 vp->v_op = &dead_vnodeops;
3909 * Print out a description of a vnode.
3911 static const char * const typename[] =
3912 {"VNON", "VREG", "VDIR", "VBLK", "VCHR", "VLNK", "VSOCK", "VFIFO", "VBAD",
3915 _Static_assert((VHOLD_ALL_FLAGS & ~VHOLD_NO_SMR) == 0,
3916 "new hold count flag not added to vn_printf");
3919 vn_printf(struct vnode *vp, const char *fmt, ...)
3922 char buf[256], buf2[16];
3929 printf("%p: ", (void *)vp);
3930 printf("type %s\n", typename[vp->v_type]);
3931 holdcnt = atomic_load_int(&vp->v_holdcnt);
3932 printf(" usecount %d, writecount %d, refcount %d seqc users %d",
3933 vp->v_usecount, vp->v_writecount, holdcnt & ~VHOLD_ALL_FLAGS,
3935 switch (vp->v_type) {
3937 printf(" mountedhere %p\n", vp->v_mountedhere);
3940 printf(" rdev %p\n", vp->v_rdev);
3943 printf(" socket %p\n", vp->v_unpcb);
3946 printf(" fifoinfo %p\n", vp->v_fifoinfo);
3954 if (holdcnt & VHOLD_NO_SMR)
3955 strlcat(buf, "|VHOLD_NO_SMR", sizeof(buf));
3956 printf(" hold count flags (%s)\n", buf + 1);
3960 if (vp->v_irflag & VIRF_DOOMED)
3961 strlcat(buf, "|VIRF_DOOMED", sizeof(buf));
3962 if (vp->v_irflag & VIRF_PGREAD)
3963 strlcat(buf, "|VIRF_PGREAD", sizeof(buf));
3964 flags = vp->v_irflag & ~(VIRF_DOOMED | VIRF_PGREAD);
3966 snprintf(buf2, sizeof(buf2), "|VIRF(0x%lx)", flags);
3967 strlcat(buf, buf2, sizeof(buf));
3969 if (vp->v_vflag & VV_ROOT)
3970 strlcat(buf, "|VV_ROOT", sizeof(buf));
3971 if (vp->v_vflag & VV_ISTTY)
3972 strlcat(buf, "|VV_ISTTY", sizeof(buf));
3973 if (vp->v_vflag & VV_NOSYNC)
3974 strlcat(buf, "|VV_NOSYNC", sizeof(buf));
3975 if (vp->v_vflag & VV_ETERNALDEV)
3976 strlcat(buf, "|VV_ETERNALDEV", sizeof(buf));
3977 if (vp->v_vflag & VV_CACHEDLABEL)
3978 strlcat(buf, "|VV_CACHEDLABEL", sizeof(buf));
3979 if (vp->v_vflag & VV_VMSIZEVNLOCK)
3980 strlcat(buf, "|VV_VMSIZEVNLOCK", sizeof(buf));
3981 if (vp->v_vflag & VV_COPYONWRITE)
3982 strlcat(buf, "|VV_COPYONWRITE", sizeof(buf));
3983 if (vp->v_vflag & VV_SYSTEM)
3984 strlcat(buf, "|VV_SYSTEM", sizeof(buf));
3985 if (vp->v_vflag & VV_PROCDEP)
3986 strlcat(buf, "|VV_PROCDEP", sizeof(buf));
3987 if (vp->v_vflag & VV_NOKNOTE)
3988 strlcat(buf, "|VV_NOKNOTE", sizeof(buf));
3989 if (vp->v_vflag & VV_DELETED)
3990 strlcat(buf, "|VV_DELETED", sizeof(buf));
3991 if (vp->v_vflag & VV_MD)
3992 strlcat(buf, "|VV_MD", sizeof(buf));
3993 if (vp->v_vflag & VV_FORCEINSMQ)
3994 strlcat(buf, "|VV_FORCEINSMQ", sizeof(buf));
3995 if (vp->v_vflag & VV_READLINK)
3996 strlcat(buf, "|VV_READLINK", sizeof(buf));
3997 flags = vp->v_vflag & ~(VV_ROOT | VV_ISTTY | VV_NOSYNC | VV_ETERNALDEV |
3998 VV_CACHEDLABEL | VV_COPYONWRITE | VV_SYSTEM | VV_PROCDEP |
3999 VV_NOKNOTE | VV_DELETED | VV_MD | VV_FORCEINSMQ);
4001 snprintf(buf2, sizeof(buf2), "|VV(0x%lx)", flags);
4002 strlcat(buf, buf2, sizeof(buf));
4004 if (vp->v_iflag & VI_TEXT_REF)
4005 strlcat(buf, "|VI_TEXT_REF", sizeof(buf));
4006 if (vp->v_iflag & VI_MOUNT)
4007 strlcat(buf, "|VI_MOUNT", sizeof(buf));
4008 if (vp->v_iflag & VI_DOINGINACT)
4009 strlcat(buf, "|VI_DOINGINACT", sizeof(buf));
4010 if (vp->v_iflag & VI_OWEINACT)
4011 strlcat(buf, "|VI_OWEINACT", sizeof(buf));
4012 if (vp->v_iflag & VI_DEFINACT)
4013 strlcat(buf, "|VI_DEFINACT", sizeof(buf));
4014 flags = vp->v_iflag & ~(VI_TEXT_REF | VI_MOUNT | VI_DOINGINACT |
4015 VI_OWEINACT | VI_DEFINACT);
4017 snprintf(buf2, sizeof(buf2), "|VI(0x%lx)", flags);
4018 strlcat(buf, buf2, sizeof(buf));
4020 if (vp->v_mflag & VMP_LAZYLIST)
4021 strlcat(buf, "|VMP_LAZYLIST", sizeof(buf));
4022 flags = vp->v_mflag & ~(VMP_LAZYLIST);
4024 snprintf(buf2, sizeof(buf2), "|VMP(0x%lx)", flags);
4025 strlcat(buf, buf2, sizeof(buf));
4027 printf(" flags (%s)\n", buf + 1);
4028 if (mtx_owned(VI_MTX(vp)))
4029 printf(" VI_LOCKed");
4030 if (vp->v_object != NULL)
4031 printf(" v_object %p ref %d pages %d "
4032 "cleanbuf %d dirtybuf %d\n",
4033 vp->v_object, vp->v_object->ref_count,
4034 vp->v_object->resident_page_count,
4035 vp->v_bufobj.bo_clean.bv_cnt,
4036 vp->v_bufobj.bo_dirty.bv_cnt);
4038 lockmgr_printinfo(vp->v_vnlock);
4039 if (vp->v_data != NULL)
4045 * List all of the locked vnodes in the system.
4046 * Called when debugging the kernel.
4048 DB_SHOW_COMMAND(lockedvnods, lockedvnodes)
4054 * Note: because this is DDB, we can't obey the locking semantics
4055 * for these structures, which means we could catch an inconsistent
4056 * state and dereference a nasty pointer. Not much to be done
4059 db_printf("Locked vnodes\n");
4060 TAILQ_FOREACH(mp, &mountlist, mnt_list) {
4061 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) {
4062 if (vp->v_type != VMARKER && VOP_ISLOCKED(vp))
4063 vn_printf(vp, "vnode ");
4069 * Show details about the given vnode.
4071 DB_SHOW_COMMAND(vnode, db_show_vnode)
4077 vp = (struct vnode *)addr;
4078 vn_printf(vp, "vnode ");
4082 * Show details about the given mount point.
4084 DB_SHOW_COMMAND(mount, db_show_mount)
4095 /* No address given, print short info about all mount points. */
4096 TAILQ_FOREACH(mp, &mountlist, mnt_list) {
4097 db_printf("%p %s on %s (%s)\n", mp,
4098 mp->mnt_stat.f_mntfromname,
4099 mp->mnt_stat.f_mntonname,
4100 mp->mnt_stat.f_fstypename);
4104 db_printf("\nMore info: show mount <addr>\n");
4108 mp = (struct mount *)addr;
4109 db_printf("%p %s on %s (%s)\n", mp, mp->mnt_stat.f_mntfromname,
4110 mp->mnt_stat.f_mntonname, mp->mnt_stat.f_fstypename);
4113 mflags = mp->mnt_flag;
4114 #define MNT_FLAG(flag) do { \
4115 if (mflags & (flag)) { \
4116 if (buf[0] != '\0') \
4117 strlcat(buf, ", ", sizeof(buf)); \
4118 strlcat(buf, (#flag) + 4, sizeof(buf)); \
4119 mflags &= ~(flag); \
4122 MNT_FLAG(MNT_RDONLY);
4123 MNT_FLAG(MNT_SYNCHRONOUS);
4124 MNT_FLAG(MNT_NOEXEC);
4125 MNT_FLAG(MNT_NOSUID);
4126 MNT_FLAG(MNT_NFS4ACLS);
4127 MNT_FLAG(MNT_UNION);
4128 MNT_FLAG(MNT_ASYNC);
4129 MNT_FLAG(MNT_SUIDDIR);
4130 MNT_FLAG(MNT_SOFTDEP);
4131 MNT_FLAG(MNT_NOSYMFOLLOW);
4132 MNT_FLAG(MNT_GJOURNAL);
4133 MNT_FLAG(MNT_MULTILABEL);
4135 MNT_FLAG(MNT_NOATIME);
4136 MNT_FLAG(MNT_NOCLUSTERR);
4137 MNT_FLAG(MNT_NOCLUSTERW);
4139 MNT_FLAG(MNT_EXRDONLY);
4140 MNT_FLAG(MNT_EXPORTED);
4141 MNT_FLAG(MNT_DEFEXPORTED);
4142 MNT_FLAG(MNT_EXPORTANON);
4143 MNT_FLAG(MNT_EXKERB);
4144 MNT_FLAG(MNT_EXPUBLIC);
4145 MNT_FLAG(MNT_LOCAL);
4146 MNT_FLAG(MNT_QUOTA);
4147 MNT_FLAG(MNT_ROOTFS);
4149 MNT_FLAG(MNT_IGNORE);
4150 MNT_FLAG(MNT_UPDATE);
4151 MNT_FLAG(MNT_DELEXPORT);
4152 MNT_FLAG(MNT_RELOAD);
4153 MNT_FLAG(MNT_FORCE);
4154 MNT_FLAG(MNT_SNAPSHOT);
4155 MNT_FLAG(MNT_BYFSID);
4159 strlcat(buf, ", ", sizeof(buf));
4160 snprintf(buf + strlen(buf), sizeof(buf) - strlen(buf),
4161 "0x%016jx", mflags);
4163 db_printf(" mnt_flag = %s\n", buf);
4166 flags = mp->mnt_kern_flag;
4167 #define MNT_KERN_FLAG(flag) do { \
4168 if (flags & (flag)) { \
4169 if (buf[0] != '\0') \
4170 strlcat(buf, ", ", sizeof(buf)); \
4171 strlcat(buf, (#flag) + 5, sizeof(buf)); \
4175 MNT_KERN_FLAG(MNTK_UNMOUNTF);
4176 MNT_KERN_FLAG(MNTK_ASYNC);
4177 MNT_KERN_FLAG(MNTK_SOFTDEP);
4178 MNT_KERN_FLAG(MNTK_DRAINING);
4179 MNT_KERN_FLAG(MNTK_REFEXPIRE);
4180 MNT_KERN_FLAG(MNTK_EXTENDED_SHARED);
4181 MNT_KERN_FLAG(MNTK_SHARED_WRITES);
4182 MNT_KERN_FLAG(MNTK_NO_IOPF);
4183 MNT_KERN_FLAG(MNTK_VGONE_UPPER);
4184 MNT_KERN_FLAG(MNTK_VGONE_WAITER);
4185 MNT_KERN_FLAG(MNTK_LOOKUP_EXCL_DOTDOT);
4186 MNT_KERN_FLAG(MNTK_MARKER);
4187 MNT_KERN_FLAG(MNTK_USES_BCACHE);
4188 MNT_KERN_FLAG(MNTK_FPLOOKUP);
4189 MNT_KERN_FLAG(MNTK_NOASYNC);
4190 MNT_KERN_FLAG(MNTK_UNMOUNT);
4191 MNT_KERN_FLAG(MNTK_MWAIT);
4192 MNT_KERN_FLAG(MNTK_SUSPEND);
4193 MNT_KERN_FLAG(MNTK_SUSPEND2);
4194 MNT_KERN_FLAG(MNTK_SUSPENDED);
4195 MNT_KERN_FLAG(MNTK_LOOKUP_SHARED);
4196 MNT_KERN_FLAG(MNTK_NOKNOTE);
4197 #undef MNT_KERN_FLAG
4200 strlcat(buf, ", ", sizeof(buf));
4201 snprintf(buf + strlen(buf), sizeof(buf) - strlen(buf),
4204 db_printf(" mnt_kern_flag = %s\n", buf);
4206 db_printf(" mnt_opt = ");
4207 opt = TAILQ_FIRST(mp->mnt_opt);
4209 db_printf("%s", opt->name);
4210 opt = TAILQ_NEXT(opt, link);
4211 while (opt != NULL) {
4212 db_printf(", %s", opt->name);
4213 opt = TAILQ_NEXT(opt, link);
4219 db_printf(" mnt_stat = { version=%u type=%u flags=0x%016jx "
4220 "bsize=%ju iosize=%ju blocks=%ju bfree=%ju bavail=%jd files=%ju "
4221 "ffree=%jd syncwrites=%ju asyncwrites=%ju syncreads=%ju "
4222 "asyncreads=%ju namemax=%u owner=%u fsid=[%d, %d] }\n",
4223 (u_int)sp->f_version, (u_int)sp->f_type, (uintmax_t)sp->f_flags,
4224 (uintmax_t)sp->f_bsize, (uintmax_t)sp->f_iosize,
4225 (uintmax_t)sp->f_blocks, (uintmax_t)sp->f_bfree,
4226 (intmax_t)sp->f_bavail, (uintmax_t)sp->f_files,
4227 (intmax_t)sp->f_ffree, (uintmax_t)sp->f_syncwrites,
4228 (uintmax_t)sp->f_asyncwrites, (uintmax_t)sp->f_syncreads,
4229 (uintmax_t)sp->f_asyncreads, (u_int)sp->f_namemax,
4230 (u_int)sp->f_owner, (int)sp->f_fsid.val[0], (int)sp->f_fsid.val[1]);
4232 db_printf(" mnt_cred = { uid=%u ruid=%u",
4233 (u_int)mp->mnt_cred->cr_uid, (u_int)mp->mnt_cred->cr_ruid);
4234 if (jailed(mp->mnt_cred))
4235 db_printf(", jail=%d", mp->mnt_cred->cr_prison->pr_id);
4237 db_printf(" mnt_ref = %d (with %d in the struct)\n",
4238 vfs_mount_fetch_counter(mp, MNT_COUNT_REF), mp->mnt_ref);
4239 db_printf(" mnt_gen = %d\n", mp->mnt_gen);
4240 db_printf(" mnt_nvnodelistsize = %d\n", mp->mnt_nvnodelistsize);
4241 db_printf(" mnt_lazyvnodelistsize = %d\n",
4242 mp->mnt_lazyvnodelistsize);
4243 db_printf(" mnt_writeopcount = %d (with %d in the struct)\n",
4244 vfs_mount_fetch_counter(mp, MNT_COUNT_WRITEOPCOUNT), mp->mnt_writeopcount);
4245 db_printf(" mnt_maxsymlinklen = %d\n", mp->mnt_maxsymlinklen);
4246 db_printf(" mnt_iosize_max = %d\n", mp->mnt_iosize_max);
4247 db_printf(" mnt_hashseed = %u\n", mp->mnt_hashseed);
4248 db_printf(" mnt_lockref = %d (with %d in the struct)\n",
4249 vfs_mount_fetch_counter(mp, MNT_COUNT_LOCKREF), mp->mnt_lockref);
4250 db_printf(" mnt_secondary_writes = %d\n", mp->mnt_secondary_writes);
4251 db_printf(" mnt_secondary_accwrites = %d\n",
4252 mp->mnt_secondary_accwrites);
4253 db_printf(" mnt_gjprovider = %s\n",
4254 mp->mnt_gjprovider != NULL ? mp->mnt_gjprovider : "NULL");
4255 db_printf(" mnt_vfs_ops = %d\n", mp->mnt_vfs_ops);
4257 db_printf("\n\nList of active vnodes\n");
4258 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) {
4259 if (vp->v_type != VMARKER && vp->v_holdcnt > 0) {
4260 vn_printf(vp, "vnode ");
4265 db_printf("\n\nList of inactive vnodes\n");
4266 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) {
4267 if (vp->v_type != VMARKER && vp->v_holdcnt == 0) {
4268 vn_printf(vp, "vnode ");
4277 * Fill in a struct xvfsconf based on a struct vfsconf.
4280 vfsconf2x(struct sysctl_req *req, struct vfsconf *vfsp)
4282 struct xvfsconf xvfsp;
4284 bzero(&xvfsp, sizeof(xvfsp));
4285 strcpy(xvfsp.vfc_name, vfsp->vfc_name);
4286 xvfsp.vfc_typenum = vfsp->vfc_typenum;
4287 xvfsp.vfc_refcount = vfsp->vfc_refcount;
4288 xvfsp.vfc_flags = vfsp->vfc_flags;
4290 * These are unused in userland, we keep them
4291 * to not break binary compatibility.
4293 xvfsp.vfc_vfsops = NULL;
4294 xvfsp.vfc_next = NULL;
4295 return (SYSCTL_OUT(req, &xvfsp, sizeof(xvfsp)));
4298 #ifdef COMPAT_FREEBSD32
4300 uint32_t vfc_vfsops;
4301 char vfc_name[MFSNAMELEN];
4302 int32_t vfc_typenum;
4303 int32_t vfc_refcount;
4309 vfsconf2x32(struct sysctl_req *req, struct vfsconf *vfsp)
4311 struct xvfsconf32 xvfsp;
4313 bzero(&xvfsp, sizeof(xvfsp));
4314 strcpy(xvfsp.vfc_name, vfsp->vfc_name);
4315 xvfsp.vfc_typenum = vfsp->vfc_typenum;
4316 xvfsp.vfc_refcount = vfsp->vfc_refcount;
4317 xvfsp.vfc_flags = vfsp->vfc_flags;
4318 return (SYSCTL_OUT(req, &xvfsp, sizeof(xvfsp)));
4323 * Top level filesystem related information gathering.
4326 sysctl_vfs_conflist(SYSCTL_HANDLER_ARGS)
4328 struct vfsconf *vfsp;
4333 TAILQ_FOREACH(vfsp, &vfsconf, vfc_list) {
4334 #ifdef COMPAT_FREEBSD32
4335 if (req->flags & SCTL_MASK32)
4336 error = vfsconf2x32(req, vfsp);
4339 error = vfsconf2x(req, vfsp);
4347 SYSCTL_PROC(_vfs, OID_AUTO, conflist, CTLTYPE_OPAQUE | CTLFLAG_RD |
4348 CTLFLAG_MPSAFE, NULL, 0, sysctl_vfs_conflist,
4349 "S,xvfsconf", "List of all configured filesystems");
4351 #ifndef BURN_BRIDGES
4352 static int sysctl_ovfs_conf(SYSCTL_HANDLER_ARGS);
4355 vfs_sysctl(SYSCTL_HANDLER_ARGS)
4357 int *name = (int *)arg1 - 1; /* XXX */
4358 u_int namelen = arg2 + 1; /* XXX */
4359 struct vfsconf *vfsp;
4361 log(LOG_WARNING, "userland calling deprecated sysctl, "
4362 "please rebuild world\n");
4364 #if 1 || defined(COMPAT_PRELITE2)
4365 /* Resolve ambiguity between VFS_VFSCONF and VFS_GENERIC. */
4367 return (sysctl_ovfs_conf(oidp, arg1, arg2, req));
4371 case VFS_MAXTYPENUM:
4374 return (SYSCTL_OUT(req, &maxvfsconf, sizeof(int)));
4377 return (ENOTDIR); /* overloaded */
4379 TAILQ_FOREACH(vfsp, &vfsconf, vfc_list) {
4380 if (vfsp->vfc_typenum == name[2])
4385 return (EOPNOTSUPP);
4386 #ifdef COMPAT_FREEBSD32
4387 if (req->flags & SCTL_MASK32)
4388 return (vfsconf2x32(req, vfsp));
4391 return (vfsconf2x(req, vfsp));
4393 return (EOPNOTSUPP);
4396 static SYSCTL_NODE(_vfs, VFS_GENERIC, generic, CTLFLAG_RD | CTLFLAG_SKIP |
4397 CTLFLAG_MPSAFE, vfs_sysctl,
4398 "Generic filesystem");
4400 #if 1 || defined(COMPAT_PRELITE2)
4403 sysctl_ovfs_conf(SYSCTL_HANDLER_ARGS)
4406 struct vfsconf *vfsp;
4407 struct ovfsconf ovfs;
4410 TAILQ_FOREACH(vfsp, &vfsconf, vfc_list) {
4411 bzero(&ovfs, sizeof(ovfs));
4412 ovfs.vfc_vfsops = vfsp->vfc_vfsops; /* XXX used as flag */
4413 strcpy(ovfs.vfc_name, vfsp->vfc_name);
4414 ovfs.vfc_index = vfsp->vfc_typenum;
4415 ovfs.vfc_refcount = vfsp->vfc_refcount;
4416 ovfs.vfc_flags = vfsp->vfc_flags;
4417 error = SYSCTL_OUT(req, &ovfs, sizeof ovfs);
4427 #endif /* 1 || COMPAT_PRELITE2 */
4428 #endif /* !BURN_BRIDGES */
4430 #define KINFO_VNODESLOP 10
4433 * Dump vnode list (via sysctl).
4437 sysctl_vnode(SYSCTL_HANDLER_ARGS)
4445 * Stale numvnodes access is not fatal here.
4448 len = (numvnodes + KINFO_VNODESLOP) * sizeof *xvn;
4450 /* Make an estimate */
4451 return (SYSCTL_OUT(req, 0, len));
4453 error = sysctl_wire_old_buffer(req, 0);
4456 xvn = malloc(len, M_TEMP, M_ZERO | M_WAITOK);
4458 mtx_lock(&mountlist_mtx);
4459 TAILQ_FOREACH(mp, &mountlist, mnt_list) {
4460 if (vfs_busy(mp, MBF_NOWAIT | MBF_MNTLSTLOCK))
4463 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) {
4467 xvn[n].xv_size = sizeof *xvn;
4468 xvn[n].xv_vnode = vp;
4469 xvn[n].xv_id = 0; /* XXX compat */
4470 #define XV_COPY(field) xvn[n].xv_##field = vp->v_##field
4472 XV_COPY(writecount);
4478 xvn[n].xv_flag = vp->v_vflag;
4480 switch (vp->v_type) {
4487 if (vp->v_rdev == NULL) {
4491 xvn[n].xv_dev = dev2udev(vp->v_rdev);
4494 xvn[n].xv_socket = vp->v_socket;
4497 xvn[n].xv_fifo = vp->v_fifoinfo;
4502 /* shouldn't happen? */
4510 mtx_lock(&mountlist_mtx);
4515 mtx_unlock(&mountlist_mtx);
4517 error = SYSCTL_OUT(req, xvn, n * sizeof *xvn);
4522 SYSCTL_PROC(_kern, KERN_VNODE, vnode, CTLTYPE_OPAQUE | CTLFLAG_RD |
4523 CTLFLAG_MPSAFE, 0, 0, sysctl_vnode, "S,xvnode",
4528 unmount_or_warn(struct mount *mp)
4532 error = dounmount(mp, MNT_FORCE, curthread);
4534 printf("unmount of %s failed (", mp->mnt_stat.f_mntonname);
4538 printf("%d)\n", error);
4543 * Unmount all filesystems. The list is traversed in reverse order
4544 * of mounting to avoid dependencies.
4547 vfs_unmountall(void)
4549 struct mount *mp, *tmp;
4551 CTR1(KTR_VFS, "%s: unmounting all filesystems", __func__);
4554 * Since this only runs when rebooting, it is not interlocked.
4556 TAILQ_FOREACH_REVERSE_SAFE(mp, &mountlist, mntlist, mnt_list, tmp) {
4560 * Forcibly unmounting "/dev" before "/" would prevent clean
4561 * unmount of the latter.
4563 if (mp == rootdevmp)
4566 unmount_or_warn(mp);
4569 if (rootdevmp != NULL)
4570 unmount_or_warn(rootdevmp);
4574 vfs_deferred_inactive(struct vnode *vp, int lkflags)
4577 ASSERT_VI_LOCKED(vp, __func__);
4578 VNASSERT((vp->v_iflag & VI_DEFINACT) == 0, vp, ("VI_DEFINACT still set"));
4579 if ((vp->v_iflag & VI_OWEINACT) == 0) {
4583 if (vn_lock(vp, lkflags) == 0) {
4590 vdefer_inactive_unlocked(vp);
4594 vfs_periodic_inactive_filter(struct vnode *vp, void *arg)
4597 return (vp->v_iflag & VI_DEFINACT);
4600 static void __noinline
4601 vfs_periodic_inactive(struct mount *mp, int flags)
4603 struct vnode *vp, *mvp;
4606 lkflags = LK_EXCLUSIVE | LK_INTERLOCK;
4607 if (flags != MNT_WAIT)
4608 lkflags |= LK_NOWAIT;
4610 MNT_VNODE_FOREACH_LAZY(vp, mp, mvp, vfs_periodic_inactive_filter, NULL) {
4611 if ((vp->v_iflag & VI_DEFINACT) == 0) {
4615 vp->v_iflag &= ~VI_DEFINACT;
4616 vfs_deferred_inactive(vp, lkflags);
4621 vfs_want_msync(struct vnode *vp)
4623 struct vm_object *obj;
4626 * This test may be performed without any locks held.
4627 * We rely on vm_object's type stability.
4629 if (vp->v_vflag & VV_NOSYNC)
4632 return (obj != NULL && vm_object_mightbedirty(obj));
4636 vfs_periodic_msync_inactive_filter(struct vnode *vp, void *arg __unused)
4639 if (vp->v_vflag & VV_NOSYNC)
4641 if (vp->v_iflag & VI_DEFINACT)
4643 return (vfs_want_msync(vp));
4646 static void __noinline
4647 vfs_periodic_msync_inactive(struct mount *mp, int flags)
4649 struct vnode *vp, *mvp;
4650 struct vm_object *obj;
4652 int lkflags, objflags;
4657 lkflags = LK_EXCLUSIVE | LK_INTERLOCK;
4658 if (flags != MNT_WAIT) {
4659 lkflags |= LK_NOWAIT;
4660 objflags = OBJPC_NOSYNC;
4662 objflags = OBJPC_SYNC;
4665 MNT_VNODE_FOREACH_LAZY(vp, mp, mvp, vfs_periodic_msync_inactive_filter, NULL) {
4667 if (vp->v_iflag & VI_DEFINACT) {
4668 vp->v_iflag &= ~VI_DEFINACT;
4671 if (!vfs_want_msync(vp)) {
4673 vfs_deferred_inactive(vp, lkflags);
4678 if (vget(vp, lkflags) == 0) {
4680 if (obj != NULL && (vp->v_vflag & VV_NOSYNC) == 0) {
4681 VM_OBJECT_WLOCK(obj);
4682 vm_object_page_clean(obj, 0, 0, objflags);
4683 VM_OBJECT_WUNLOCK(obj);
4690 vdefer_inactive_unlocked(vp);
4696 vfs_periodic(struct mount *mp, int flags)
4699 CTR2(KTR_VFS, "%s: mp %p", __func__, mp);
4701 if ((mp->mnt_kern_flag & MNTK_NOMSYNC) != 0)
4702 vfs_periodic_inactive(mp, flags);
4704 vfs_periodic_msync_inactive(mp, flags);
4708 destroy_vpollinfo_free(struct vpollinfo *vi)
4711 knlist_destroy(&vi->vpi_selinfo.si_note);
4712 mtx_destroy(&vi->vpi_lock);
4713 uma_zfree(vnodepoll_zone, vi);
4717 destroy_vpollinfo(struct vpollinfo *vi)
4720 knlist_clear(&vi->vpi_selinfo.si_note, 1);
4721 seldrain(&vi->vpi_selinfo);
4722 destroy_vpollinfo_free(vi);
4726 * Initialize per-vnode helper structure to hold poll-related state.
4729 v_addpollinfo(struct vnode *vp)
4731 struct vpollinfo *vi;
4733 if (vp->v_pollinfo != NULL)
4735 vi = uma_zalloc(vnodepoll_zone, M_WAITOK | M_ZERO);
4736 mtx_init(&vi->vpi_lock, "vnode pollinfo", NULL, MTX_DEF);
4737 knlist_init(&vi->vpi_selinfo.si_note, vp, vfs_knllock,
4738 vfs_knlunlock, vfs_knl_assert_locked, vfs_knl_assert_unlocked);
4740 if (vp->v_pollinfo != NULL) {
4742 destroy_vpollinfo_free(vi);
4745 vp->v_pollinfo = vi;
4750 * Record a process's interest in events which might happen to
4751 * a vnode. Because poll uses the historic select-style interface
4752 * internally, this routine serves as both the ``check for any
4753 * pending events'' and the ``record my interest in future events''
4754 * functions. (These are done together, while the lock is held,
4755 * to avoid race conditions.)
4758 vn_pollrecord(struct vnode *vp, struct thread *td, int events)
4762 mtx_lock(&vp->v_pollinfo->vpi_lock);
4763 if (vp->v_pollinfo->vpi_revents & events) {
4765 * This leaves events we are not interested
4766 * in available for the other process which
4767 * which presumably had requested them
4768 * (otherwise they would never have been
4771 events &= vp->v_pollinfo->vpi_revents;
4772 vp->v_pollinfo->vpi_revents &= ~events;
4774 mtx_unlock(&vp->v_pollinfo->vpi_lock);
4777 vp->v_pollinfo->vpi_events |= events;
4778 selrecord(td, &vp->v_pollinfo->vpi_selinfo);
4779 mtx_unlock(&vp->v_pollinfo->vpi_lock);
4784 * Routine to create and manage a filesystem syncer vnode.
4786 #define sync_close ((int (*)(struct vop_close_args *))nullop)
4787 static int sync_fsync(struct vop_fsync_args *);
4788 static int sync_inactive(struct vop_inactive_args *);
4789 static int sync_reclaim(struct vop_reclaim_args *);
4791 static struct vop_vector sync_vnodeops = {
4792 .vop_bypass = VOP_EOPNOTSUPP,
4793 .vop_close = sync_close, /* close */
4794 .vop_fsync = sync_fsync, /* fsync */
4795 .vop_inactive = sync_inactive, /* inactive */
4796 .vop_need_inactive = vop_stdneed_inactive, /* need_inactive */
4797 .vop_reclaim = sync_reclaim, /* reclaim */
4798 .vop_lock1 = vop_stdlock, /* lock */
4799 .vop_unlock = vop_stdunlock, /* unlock */
4800 .vop_islocked = vop_stdislocked, /* islocked */
4802 VFS_VOP_VECTOR_REGISTER(sync_vnodeops);
4805 * Create a new filesystem syncer vnode for the specified mount point.
4808 vfs_allocate_syncvnode(struct mount *mp)
4812 static long start, incr, next;
4815 /* Allocate a new vnode */
4816 error = getnewvnode("syncer", mp, &sync_vnodeops, &vp);
4818 panic("vfs_allocate_syncvnode: getnewvnode() failed");
4820 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
4821 vp->v_vflag |= VV_FORCEINSMQ;
4822 error = insmntque(vp, mp);
4824 panic("vfs_allocate_syncvnode: insmntque() failed");
4825 vp->v_vflag &= ~VV_FORCEINSMQ;
4828 * Place the vnode onto the syncer worklist. We attempt to
4829 * scatter them about on the list so that they will go off
4830 * at evenly distributed times even if all the filesystems
4831 * are mounted at once.
4834 if (next == 0 || next > syncer_maxdelay) {
4838 start = syncer_maxdelay / 2;
4839 incr = syncer_maxdelay;
4845 vn_syncer_add_to_worklist(bo, syncdelay > 0 ? next % syncdelay : 0);
4846 /* XXX - vn_syncer_add_to_worklist() also grabs and drops sync_mtx. */
4847 mtx_lock(&sync_mtx);
4849 if (mp->mnt_syncer == NULL) {
4850 mp->mnt_syncer = vp;
4853 mtx_unlock(&sync_mtx);
4856 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
4863 vfs_deallocate_syncvnode(struct mount *mp)
4867 mtx_lock(&sync_mtx);
4868 vp = mp->mnt_syncer;
4870 mp->mnt_syncer = NULL;
4871 mtx_unlock(&sync_mtx);
4877 * Do a lazy sync of the filesystem.
4880 sync_fsync(struct vop_fsync_args *ap)
4882 struct vnode *syncvp = ap->a_vp;
4883 struct mount *mp = syncvp->v_mount;
4888 * We only need to do something if this is a lazy evaluation.
4890 if (ap->a_waitfor != MNT_LAZY)
4894 * Move ourselves to the back of the sync list.
4896 bo = &syncvp->v_bufobj;
4898 vn_syncer_add_to_worklist(bo, syncdelay);
4902 * Walk the list of vnodes pushing all that are dirty and
4903 * not already on the sync list.
4905 if (vfs_busy(mp, MBF_NOWAIT) != 0)
4907 if (vn_start_write(NULL, &mp, V_NOWAIT) != 0) {
4911 save = curthread_pflags_set(TDP_SYNCIO);
4913 * The filesystem at hand may be idle with free vnodes stored in the
4914 * batch. Return them instead of letting them stay there indefinitely.
4916 vfs_periodic(mp, MNT_NOWAIT);
4917 error = VFS_SYNC(mp, MNT_LAZY);
4918 curthread_pflags_restore(save);
4919 vn_finished_write(mp);
4925 * The syncer vnode is no referenced.
4928 sync_inactive(struct vop_inactive_args *ap)
4936 * The syncer vnode is no longer needed and is being decommissioned.
4938 * Modifications to the worklist must be protected by sync_mtx.
4941 sync_reclaim(struct vop_reclaim_args *ap)
4943 struct vnode *vp = ap->a_vp;
4948 mtx_lock(&sync_mtx);
4949 if (vp->v_mount->mnt_syncer == vp)
4950 vp->v_mount->mnt_syncer = NULL;
4951 if (bo->bo_flag & BO_ONWORKLST) {
4952 LIST_REMOVE(bo, bo_synclist);
4953 syncer_worklist_len--;
4955 bo->bo_flag &= ~BO_ONWORKLST;
4957 mtx_unlock(&sync_mtx);
4964 vn_need_pageq_flush(struct vnode *vp)
4966 struct vm_object *obj;
4969 MPASS(mtx_owned(VI_MTX(vp)));
4971 if ((obj = vp->v_object) != NULL && (vp->v_vflag & VV_NOSYNC) == 0 &&
4972 vm_object_mightbedirty(obj))
4978 * Check if vnode represents a disk device
4981 vn_isdisk_error(struct vnode *vp, int *errp)
4985 if (vp->v_type != VCHR) {
4991 if (vp->v_rdev == NULL)
4993 else if (vp->v_rdev->si_devsw == NULL)
4995 else if (!(vp->v_rdev->si_devsw->d_flags & D_DISK))
5000 return (error == 0);
5004 vn_isdisk(struct vnode *vp)
5008 return (vn_isdisk_error(vp, &error));
5012 * VOP_FPLOOKUP_VEXEC routines are subject to special circumstances, see
5013 * the comment above cache_fplookup for details.
5015 * We never deny as priv_check_cred calls are not yet supported, see vaccess.
5018 vaccess_vexec_smr(mode_t file_mode, uid_t file_uid, gid_t file_gid, struct ucred *cred)
5021 VFS_SMR_ASSERT_ENTERED();
5023 /* Check the owner. */
5024 if (cred->cr_uid == file_uid) {
5025 if (file_mode & S_IXUSR)
5030 /* Otherwise, check the groups (first match) */
5031 if (groupmember(file_gid, cred)) {
5032 if (file_mode & S_IXGRP)
5037 /* Otherwise, check everyone else. */
5038 if (file_mode & S_IXOTH)
5044 * Common filesystem object access control check routine. Accepts a
5045 * vnode's type, "mode", uid and gid, requested access mode, and credentials.
5046 * Returns 0 on success, or an errno on failure.
5049 vaccess(enum vtype type, mode_t file_mode, uid_t file_uid, gid_t file_gid,
5050 accmode_t accmode, struct ucred *cred)
5052 accmode_t dac_granted;
5053 accmode_t priv_granted;
5055 KASSERT((accmode & ~(VEXEC | VWRITE | VREAD | VADMIN | VAPPEND)) == 0,
5056 ("invalid bit in accmode"));
5057 KASSERT((accmode & VAPPEND) == 0 || (accmode & VWRITE),
5058 ("VAPPEND without VWRITE"));
5061 * Look for a normal, non-privileged way to access the file/directory
5062 * as requested. If it exists, go with that.
5067 /* Check the owner. */
5068 if (cred->cr_uid == file_uid) {
5069 dac_granted |= VADMIN;
5070 if (file_mode & S_IXUSR)
5071 dac_granted |= VEXEC;
5072 if (file_mode & S_IRUSR)
5073 dac_granted |= VREAD;
5074 if (file_mode & S_IWUSR)
5075 dac_granted |= (VWRITE | VAPPEND);
5077 if ((accmode & dac_granted) == accmode)
5083 /* Otherwise, check the groups (first match) */
5084 if (groupmember(file_gid, cred)) {
5085 if (file_mode & S_IXGRP)
5086 dac_granted |= VEXEC;
5087 if (file_mode & S_IRGRP)
5088 dac_granted |= VREAD;
5089 if (file_mode & S_IWGRP)
5090 dac_granted |= (VWRITE | VAPPEND);
5092 if ((accmode & dac_granted) == accmode)
5098 /* Otherwise, check everyone else. */
5099 if (file_mode & S_IXOTH)
5100 dac_granted |= VEXEC;
5101 if (file_mode & S_IROTH)
5102 dac_granted |= VREAD;
5103 if (file_mode & S_IWOTH)
5104 dac_granted |= (VWRITE | VAPPEND);
5105 if ((accmode & dac_granted) == accmode)
5110 * Build a privilege mask to determine if the set of privileges
5111 * satisfies the requirements when combined with the granted mask
5112 * from above. For each privilege, if the privilege is required,
5113 * bitwise or the request type onto the priv_granted mask.
5119 * For directories, use PRIV_VFS_LOOKUP to satisfy VEXEC
5120 * requests, instead of PRIV_VFS_EXEC.
5122 if ((accmode & VEXEC) && ((dac_granted & VEXEC) == 0) &&
5123 !priv_check_cred(cred, PRIV_VFS_LOOKUP))
5124 priv_granted |= VEXEC;
5127 * Ensure that at least one execute bit is on. Otherwise,
5128 * a privileged user will always succeed, and we don't want
5129 * this to happen unless the file really is executable.
5131 if ((accmode & VEXEC) && ((dac_granted & VEXEC) == 0) &&
5132 (file_mode & (S_IXUSR | S_IXGRP | S_IXOTH)) != 0 &&
5133 !priv_check_cred(cred, PRIV_VFS_EXEC))
5134 priv_granted |= VEXEC;
5137 if ((accmode & VREAD) && ((dac_granted & VREAD) == 0) &&
5138 !priv_check_cred(cred, PRIV_VFS_READ))
5139 priv_granted |= VREAD;
5141 if ((accmode & VWRITE) && ((dac_granted & VWRITE) == 0) &&
5142 !priv_check_cred(cred, PRIV_VFS_WRITE))
5143 priv_granted |= (VWRITE | VAPPEND);
5145 if ((accmode & VADMIN) && ((dac_granted & VADMIN) == 0) &&
5146 !priv_check_cred(cred, PRIV_VFS_ADMIN))
5147 priv_granted |= VADMIN;
5149 if ((accmode & (priv_granted | dac_granted)) == accmode) {
5153 return ((accmode & VADMIN) ? EPERM : EACCES);
5157 * Credential check based on process requesting service, and per-attribute
5161 extattr_check_cred(struct vnode *vp, int attrnamespace, struct ucred *cred,
5162 struct thread *td, accmode_t accmode)
5166 * Kernel-invoked always succeeds.
5172 * Do not allow privileged processes in jail to directly manipulate
5173 * system attributes.
5175 switch (attrnamespace) {
5176 case EXTATTR_NAMESPACE_SYSTEM:
5177 /* Potentially should be: return (EPERM); */
5178 return (priv_check_cred(cred, PRIV_VFS_EXTATTR_SYSTEM));
5179 case EXTATTR_NAMESPACE_USER:
5180 return (VOP_ACCESS(vp, accmode, cred, td));
5186 #ifdef DEBUG_VFS_LOCKS
5188 * This only exists to suppress warnings from unlocked specfs accesses. It is
5189 * no longer ok to have an unlocked VFS.
5191 #define IGNORE_LOCK(vp) (KERNEL_PANICKED() || (vp) == NULL || \
5192 (vp)->v_type == VCHR || (vp)->v_type == VBAD)
5194 int vfs_badlock_ddb = 1; /* Drop into debugger on violation. */
5195 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_ddb, CTLFLAG_RW, &vfs_badlock_ddb, 0,
5196 "Drop into debugger on lock violation");
5198 int vfs_badlock_mutex = 1; /* Check for interlock across VOPs. */
5199 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_mutex, CTLFLAG_RW, &vfs_badlock_mutex,
5200 0, "Check for interlock across VOPs");
5202 int vfs_badlock_print = 1; /* Print lock violations. */
5203 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_print, CTLFLAG_RW, &vfs_badlock_print,
5204 0, "Print lock violations");
5206 int vfs_badlock_vnode = 1; /* Print vnode details on lock violations. */
5207 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_vnode, CTLFLAG_RW, &vfs_badlock_vnode,
5208 0, "Print vnode details on lock violations");
5211 int vfs_badlock_backtrace = 1; /* Print backtrace at lock violations. */
5212 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_backtrace, CTLFLAG_RW,
5213 &vfs_badlock_backtrace, 0, "Print backtrace at lock violations");
5217 vfs_badlock(const char *msg, const char *str, struct vnode *vp)
5221 if (vfs_badlock_backtrace)
5224 if (vfs_badlock_vnode)
5225 vn_printf(vp, "vnode ");
5226 if (vfs_badlock_print)
5227 printf("%s: %p %s\n", str, (void *)vp, msg);
5228 if (vfs_badlock_ddb)
5229 kdb_enter(KDB_WHY_VFSLOCK, "lock violation");
5233 assert_vi_locked(struct vnode *vp, const char *str)
5236 if (vfs_badlock_mutex && !mtx_owned(VI_MTX(vp)))
5237 vfs_badlock("interlock is not locked but should be", str, vp);
5241 assert_vi_unlocked(struct vnode *vp, const char *str)
5244 if (vfs_badlock_mutex && mtx_owned(VI_MTX(vp)))
5245 vfs_badlock("interlock is locked but should not be", str, vp);
5249 assert_vop_locked(struct vnode *vp, const char *str)
5253 if (!IGNORE_LOCK(vp)) {
5254 locked = VOP_ISLOCKED(vp);
5255 if (locked == 0 || locked == LK_EXCLOTHER)
5256 vfs_badlock("is not locked but should be", str, vp);
5261 assert_vop_unlocked(struct vnode *vp, const char *str)
5264 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) == LK_EXCLUSIVE)
5265 vfs_badlock("is locked but should not be", str, vp);
5269 assert_vop_elocked(struct vnode *vp, const char *str)
5272 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) != LK_EXCLUSIVE)
5273 vfs_badlock("is not exclusive locked but should be", str, vp);
5275 #endif /* DEBUG_VFS_LOCKS */
5278 vop_rename_fail(struct vop_rename_args *ap)
5281 if (ap->a_tvp != NULL)
5283 if (ap->a_tdvp == ap->a_tvp)
5292 vop_rename_pre(void *ap)
5294 struct vop_rename_args *a = ap;
5296 #ifdef DEBUG_VFS_LOCKS
5298 ASSERT_VI_UNLOCKED(a->a_tvp, "VOP_RENAME");
5299 ASSERT_VI_UNLOCKED(a->a_tdvp, "VOP_RENAME");
5300 ASSERT_VI_UNLOCKED(a->a_fvp, "VOP_RENAME");
5301 ASSERT_VI_UNLOCKED(a->a_fdvp, "VOP_RENAME");
5303 /* Check the source (from). */
5304 if (a->a_tdvp->v_vnlock != a->a_fdvp->v_vnlock &&
5305 (a->a_tvp == NULL || a->a_tvp->v_vnlock != a->a_fdvp->v_vnlock))
5306 ASSERT_VOP_UNLOCKED(a->a_fdvp, "vop_rename: fdvp locked");
5307 if (a->a_tvp == NULL || a->a_tvp->v_vnlock != a->a_fvp->v_vnlock)
5308 ASSERT_VOP_UNLOCKED(a->a_fvp, "vop_rename: fvp locked");
5310 /* Check the target. */
5312 ASSERT_VOP_LOCKED(a->a_tvp, "vop_rename: tvp not locked");
5313 ASSERT_VOP_LOCKED(a->a_tdvp, "vop_rename: tdvp not locked");
5316 * It may be tempting to add vn_seqc_write_begin/end calls here and
5317 * in vop_rename_post but that's not going to work out since some
5318 * filesystems relookup vnodes mid-rename. This is probably a bug.
5320 * For now filesystems are expected to do the relevant calls after they
5321 * decide what vnodes to operate on.
5323 if (a->a_tdvp != a->a_fdvp)
5325 if (a->a_tvp != a->a_fvp)
5332 #ifdef DEBUG_VFS_LOCKS
5334 vop_fplookup_vexec_debugpre(void *ap __unused)
5337 VFS_SMR_ASSERT_ENTERED();
5341 vop_fplookup_vexec_debugpost(void *ap __unused, int rc __unused)
5344 VFS_SMR_ASSERT_ENTERED();
5348 vop_strategy_debugpre(void *ap)
5350 struct vop_strategy_args *a;
5357 * Cluster ops lock their component buffers but not the IO container.
5359 if ((bp->b_flags & B_CLUSTER) != 0)
5362 if (!KERNEL_PANICKED() && !BUF_ISLOCKED(bp)) {
5363 if (vfs_badlock_print)
5365 "VOP_STRATEGY: bp is not locked but should be\n");
5366 if (vfs_badlock_ddb)
5367 kdb_enter(KDB_WHY_VFSLOCK, "lock violation");
5372 vop_lock_debugpre(void *ap)
5374 struct vop_lock1_args *a = ap;
5376 if ((a->a_flags & LK_INTERLOCK) == 0)
5377 ASSERT_VI_UNLOCKED(a->a_vp, "VOP_LOCK");
5379 ASSERT_VI_LOCKED(a->a_vp, "VOP_LOCK");
5383 vop_lock_debugpost(void *ap, int rc)
5385 struct vop_lock1_args *a = ap;
5387 ASSERT_VI_UNLOCKED(a->a_vp, "VOP_LOCK");
5388 if (rc == 0 && (a->a_flags & LK_EXCLOTHER) == 0)
5389 ASSERT_VOP_LOCKED(a->a_vp, "VOP_LOCK");
5393 vop_unlock_debugpre(void *ap)
5395 struct vop_unlock_args *a = ap;
5397 ASSERT_VOP_LOCKED(a->a_vp, "VOP_UNLOCK");
5401 vop_need_inactive_debugpre(void *ap)
5403 struct vop_need_inactive_args *a = ap;
5405 ASSERT_VI_LOCKED(a->a_vp, "VOP_NEED_INACTIVE");
5409 vop_need_inactive_debugpost(void *ap, int rc)
5411 struct vop_need_inactive_args *a = ap;
5413 ASSERT_VI_LOCKED(a->a_vp, "VOP_NEED_INACTIVE");
5418 vop_create_pre(void *ap)
5420 struct vop_create_args *a;
5425 vn_seqc_write_begin(dvp);
5429 vop_create_post(void *ap, int rc)
5431 struct vop_create_args *a;
5436 vn_seqc_write_end(dvp);
5438 VFS_KNOTE_LOCKED(dvp, NOTE_WRITE);
5442 vop_whiteout_pre(void *ap)
5444 struct vop_whiteout_args *a;
5449 vn_seqc_write_begin(dvp);
5453 vop_whiteout_post(void *ap, int rc)
5455 struct vop_whiteout_args *a;
5460 vn_seqc_write_end(dvp);
5464 vop_deleteextattr_pre(void *ap)
5466 struct vop_deleteextattr_args *a;
5471 vn_seqc_write_begin(vp);
5475 vop_deleteextattr_post(void *ap, int rc)
5477 struct vop_deleteextattr_args *a;
5482 vn_seqc_write_end(vp);
5484 VFS_KNOTE_LOCKED(a->a_vp, NOTE_ATTRIB);
5488 vop_link_pre(void *ap)
5490 struct vop_link_args *a;
5491 struct vnode *vp, *tdvp;
5496 vn_seqc_write_begin(vp);
5497 vn_seqc_write_begin(tdvp);
5501 vop_link_post(void *ap, int rc)
5503 struct vop_link_args *a;
5504 struct vnode *vp, *tdvp;
5509 vn_seqc_write_end(vp);
5510 vn_seqc_write_end(tdvp);
5512 VFS_KNOTE_LOCKED(vp, NOTE_LINK);
5513 VFS_KNOTE_LOCKED(tdvp, NOTE_WRITE);
5518 vop_mkdir_pre(void *ap)
5520 struct vop_mkdir_args *a;
5525 vn_seqc_write_begin(dvp);
5529 vop_mkdir_post(void *ap, int rc)
5531 struct vop_mkdir_args *a;
5536 vn_seqc_write_end(dvp);
5538 VFS_KNOTE_LOCKED(dvp, NOTE_WRITE | NOTE_LINK);
5542 vop_mknod_pre(void *ap)
5544 struct vop_mknod_args *a;
5549 vn_seqc_write_begin(dvp);
5553 vop_mknod_post(void *ap, int rc)
5555 struct vop_mknod_args *a;
5560 vn_seqc_write_end(dvp);
5562 VFS_KNOTE_LOCKED(dvp, NOTE_WRITE);
5566 vop_reclaim_post(void *ap, int rc)
5568 struct vop_reclaim_args *a;
5573 ASSERT_VOP_IN_SEQC(vp);
5575 VFS_KNOTE_LOCKED(vp, NOTE_REVOKE);
5579 vop_remove_pre(void *ap)
5581 struct vop_remove_args *a;
5582 struct vnode *dvp, *vp;
5587 vn_seqc_write_begin(dvp);
5588 vn_seqc_write_begin(vp);
5592 vop_remove_post(void *ap, int rc)
5594 struct vop_remove_args *a;
5595 struct vnode *dvp, *vp;
5600 vn_seqc_write_end(dvp);
5601 vn_seqc_write_end(vp);
5603 VFS_KNOTE_LOCKED(dvp, NOTE_WRITE);
5604 VFS_KNOTE_LOCKED(vp, NOTE_DELETE);
5609 vop_rename_post(void *ap, int rc)
5611 struct vop_rename_args *a = ap;
5616 if (a->a_fdvp == a->a_tdvp) {
5617 if (a->a_tvp != NULL && a->a_tvp->v_type == VDIR)
5619 VFS_KNOTE_UNLOCKED(a->a_fdvp, hint);
5620 VFS_KNOTE_UNLOCKED(a->a_tdvp, hint);
5622 hint |= NOTE_EXTEND;
5623 if (a->a_fvp->v_type == VDIR)
5625 VFS_KNOTE_UNLOCKED(a->a_fdvp, hint);
5627 if (a->a_fvp->v_type == VDIR && a->a_tvp != NULL &&
5628 a->a_tvp->v_type == VDIR)
5630 VFS_KNOTE_UNLOCKED(a->a_tdvp, hint);
5633 VFS_KNOTE_UNLOCKED(a->a_fvp, NOTE_RENAME);
5635 VFS_KNOTE_UNLOCKED(a->a_tvp, NOTE_DELETE);
5637 if (a->a_tdvp != a->a_fdvp)
5639 if (a->a_tvp != a->a_fvp)
5647 vop_rmdir_pre(void *ap)
5649 struct vop_rmdir_args *a;
5650 struct vnode *dvp, *vp;
5655 vn_seqc_write_begin(dvp);
5656 vn_seqc_write_begin(vp);
5660 vop_rmdir_post(void *ap, int rc)
5662 struct vop_rmdir_args *a;
5663 struct vnode *dvp, *vp;
5668 vn_seqc_write_end(dvp);
5669 vn_seqc_write_end(vp);
5671 VFS_KNOTE_LOCKED(dvp, NOTE_WRITE | NOTE_LINK);
5672 VFS_KNOTE_LOCKED(vp, NOTE_DELETE);
5677 vop_setattr_pre(void *ap)
5679 struct vop_setattr_args *a;
5684 vn_seqc_write_begin(vp);
5688 vop_setattr_post(void *ap, int rc)
5690 struct vop_setattr_args *a;
5695 vn_seqc_write_end(vp);
5697 VFS_KNOTE_LOCKED(vp, NOTE_ATTRIB);
5701 vop_setacl_pre(void *ap)
5703 struct vop_setacl_args *a;
5708 vn_seqc_write_begin(vp);
5712 vop_setacl_post(void *ap, int rc __unused)
5714 struct vop_setacl_args *a;
5719 vn_seqc_write_end(vp);
5723 vop_setextattr_pre(void *ap)
5725 struct vop_setextattr_args *a;
5730 vn_seqc_write_begin(vp);
5734 vop_setextattr_post(void *ap, int rc)
5736 struct vop_setextattr_args *a;
5741 vn_seqc_write_end(vp);
5743 VFS_KNOTE_LOCKED(vp, NOTE_ATTRIB);
5747 vop_symlink_pre(void *ap)
5749 struct vop_symlink_args *a;
5754 vn_seqc_write_begin(dvp);
5758 vop_symlink_post(void *ap, int rc)
5760 struct vop_symlink_args *a;
5765 vn_seqc_write_end(dvp);
5767 VFS_KNOTE_LOCKED(dvp, NOTE_WRITE);
5771 vop_open_post(void *ap, int rc)
5773 struct vop_open_args *a = ap;
5776 VFS_KNOTE_LOCKED(a->a_vp, NOTE_OPEN);
5780 vop_close_post(void *ap, int rc)
5782 struct vop_close_args *a = ap;
5784 if (!rc && (a->a_cred != NOCRED || /* filter out revokes */
5785 !VN_IS_DOOMED(a->a_vp))) {
5786 VFS_KNOTE_LOCKED(a->a_vp, (a->a_fflag & FWRITE) != 0 ?
5787 NOTE_CLOSE_WRITE : NOTE_CLOSE);
5792 vop_read_post(void *ap, int rc)
5794 struct vop_read_args *a = ap;
5797 VFS_KNOTE_LOCKED(a->a_vp, NOTE_READ);
5801 vop_readdir_post(void *ap, int rc)
5803 struct vop_readdir_args *a = ap;
5806 VFS_KNOTE_LOCKED(a->a_vp, NOTE_READ);
5809 static struct knlist fs_knlist;
5812 vfs_event_init(void *arg)
5814 knlist_init_mtx(&fs_knlist, NULL);
5816 /* XXX - correct order? */
5817 SYSINIT(vfs_knlist, SI_SUB_VFS, SI_ORDER_ANY, vfs_event_init, NULL);
5820 vfs_event_signal(fsid_t *fsid, uint32_t event, intptr_t data __unused)
5823 KNOTE_UNLOCKED(&fs_knlist, event);
5826 static int filt_fsattach(struct knote *kn);
5827 static void filt_fsdetach(struct knote *kn);
5828 static int filt_fsevent(struct knote *kn, long hint);
5830 struct filterops fs_filtops = {
5832 .f_attach = filt_fsattach,
5833 .f_detach = filt_fsdetach,
5834 .f_event = filt_fsevent
5838 filt_fsattach(struct knote *kn)
5841 kn->kn_flags |= EV_CLEAR;
5842 knlist_add(&fs_knlist, kn, 0);
5847 filt_fsdetach(struct knote *kn)
5850 knlist_remove(&fs_knlist, kn, 0);
5854 filt_fsevent(struct knote *kn, long hint)
5857 kn->kn_fflags |= hint;
5858 return (kn->kn_fflags != 0);
5862 sysctl_vfs_ctl(SYSCTL_HANDLER_ARGS)
5868 error = SYSCTL_IN(req, &vc, sizeof(vc));
5871 if (vc.vc_vers != VFS_CTL_VERS1)
5873 mp = vfs_getvfs(&vc.vc_fsid);
5876 /* ensure that a specific sysctl goes to the right filesystem. */
5877 if (strcmp(vc.vc_fstypename, "*") != 0 &&
5878 strcmp(vc.vc_fstypename, mp->mnt_vfc->vfc_name) != 0) {
5882 VCTLTOREQ(&vc, req);
5883 error = VFS_SYSCTL(mp, vc.vc_op, req);
5888 SYSCTL_PROC(_vfs, OID_AUTO, ctl, CTLTYPE_OPAQUE | CTLFLAG_MPSAFE | CTLFLAG_WR,
5889 NULL, 0, sysctl_vfs_ctl, "",
5893 * Function to initialize a va_filerev field sensibly.
5894 * XXX: Wouldn't a random number make a lot more sense ??
5897 init_va_filerev(void)
5902 return (((u_quad_t)bt.sec << 32LL) | (bt.frac >> 32LL));
5905 static int filt_vfsread(struct knote *kn, long hint);
5906 static int filt_vfswrite(struct knote *kn, long hint);
5907 static int filt_vfsvnode(struct knote *kn, long hint);
5908 static void filt_vfsdetach(struct knote *kn);
5909 static struct filterops vfsread_filtops = {
5911 .f_detach = filt_vfsdetach,
5912 .f_event = filt_vfsread
5914 static struct filterops vfswrite_filtops = {
5916 .f_detach = filt_vfsdetach,
5917 .f_event = filt_vfswrite
5919 static struct filterops vfsvnode_filtops = {
5921 .f_detach = filt_vfsdetach,
5922 .f_event = filt_vfsvnode
5926 vfs_knllock(void *arg)
5928 struct vnode *vp = arg;
5930 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
5934 vfs_knlunlock(void *arg)
5936 struct vnode *vp = arg;
5942 vfs_knl_assert_locked(void *arg)
5944 #ifdef DEBUG_VFS_LOCKS
5945 struct vnode *vp = arg;
5947 ASSERT_VOP_LOCKED(vp, "vfs_knl_assert_locked");
5952 vfs_knl_assert_unlocked(void *arg)
5954 #ifdef DEBUG_VFS_LOCKS
5955 struct vnode *vp = arg;
5957 ASSERT_VOP_UNLOCKED(vp, "vfs_knl_assert_unlocked");
5962 vfs_kqfilter(struct vop_kqfilter_args *ap)
5964 struct vnode *vp = ap->a_vp;
5965 struct knote *kn = ap->a_kn;
5968 switch (kn->kn_filter) {
5970 kn->kn_fop = &vfsread_filtops;
5973 kn->kn_fop = &vfswrite_filtops;
5976 kn->kn_fop = &vfsvnode_filtops;
5982 kn->kn_hook = (caddr_t)vp;
5985 if (vp->v_pollinfo == NULL)
5987 knl = &vp->v_pollinfo->vpi_selinfo.si_note;
5989 knlist_add(knl, kn, 0);
5995 * Detach knote from vnode
5998 filt_vfsdetach(struct knote *kn)
6000 struct vnode *vp = (struct vnode *)kn->kn_hook;
6002 KASSERT(vp->v_pollinfo != NULL, ("Missing v_pollinfo"));
6003 knlist_remove(&vp->v_pollinfo->vpi_selinfo.si_note, kn, 0);
6009 filt_vfsread(struct knote *kn, long hint)
6011 struct vnode *vp = (struct vnode *)kn->kn_hook;
6016 * filesystem is gone, so set the EOF flag and schedule
6017 * the knote for deletion.
6019 if (hint == NOTE_REVOKE || (hint == 0 && vp->v_type == VBAD)) {
6021 kn->kn_flags |= (EV_EOF | EV_ONESHOT);
6026 if (VOP_GETATTR(vp, &va, curthread->td_ucred))
6030 kn->kn_data = va.va_size - kn->kn_fp->f_offset;
6031 res = (kn->kn_sfflags & NOTE_FILE_POLL) != 0 || kn->kn_data != 0;
6038 filt_vfswrite(struct knote *kn, long hint)
6040 struct vnode *vp = (struct vnode *)kn->kn_hook;
6045 * filesystem is gone, so set the EOF flag and schedule
6046 * the knote for deletion.
6048 if (hint == NOTE_REVOKE || (hint == 0 && vp->v_type == VBAD))
6049 kn->kn_flags |= (EV_EOF | EV_ONESHOT);
6057 filt_vfsvnode(struct knote *kn, long hint)
6059 struct vnode *vp = (struct vnode *)kn->kn_hook;
6063 if (kn->kn_sfflags & hint)
6064 kn->kn_fflags |= hint;
6065 if (hint == NOTE_REVOKE || (hint == 0 && vp->v_type == VBAD)) {
6066 kn->kn_flags |= EV_EOF;
6070 res = (kn->kn_fflags != 0);
6076 * Returns whether the directory is empty or not.
6077 * If it is empty, the return value is 0; otherwise
6078 * the return value is an error value (which may
6082 vfs_emptydir(struct vnode *vp)
6086 struct dirent *dirent, *dp, *endp;
6092 ASSERT_VOP_LOCKED(vp, "vfs_emptydir");
6094 dirent = malloc(sizeof(struct dirent), M_TEMP, M_WAITOK);
6095 iov.iov_base = dirent;
6096 iov.iov_len = sizeof(struct dirent);
6101 uio.uio_resid = sizeof(struct dirent);
6102 uio.uio_segflg = UIO_SYSSPACE;
6103 uio.uio_rw = UIO_READ;
6104 uio.uio_td = curthread;
6106 while (eof == 0 && error == 0) {
6107 error = VOP_READDIR(vp, &uio, curthread->td_ucred, &eof,
6111 endp = (void *)((uint8_t *)dirent +
6112 sizeof(struct dirent) - uio.uio_resid);
6113 for (dp = dirent; dp < endp;
6114 dp = (void *)((uint8_t *)dp + GENERIC_DIRSIZ(dp))) {
6115 if (dp->d_type == DT_WHT)
6117 if (dp->d_namlen == 0)
6119 if (dp->d_type != DT_DIR &&
6120 dp->d_type != DT_UNKNOWN) {
6124 if (dp->d_namlen > 2) {
6128 if (dp->d_namlen == 1 &&
6129 dp->d_name[0] != '.') {
6133 if (dp->d_namlen == 2 &&
6134 dp->d_name[1] != '.') {
6138 uio.uio_resid = sizeof(struct dirent);
6141 free(dirent, M_TEMP);
6146 vfs_read_dirent(struct vop_readdir_args *ap, struct dirent *dp, off_t off)
6150 if (dp->d_reclen > ap->a_uio->uio_resid)
6151 return (ENAMETOOLONG);
6152 error = uiomove(dp, dp->d_reclen, ap->a_uio);
6154 if (ap->a_ncookies != NULL) {
6155 if (ap->a_cookies != NULL)
6156 free(ap->a_cookies, M_TEMP);
6157 ap->a_cookies = NULL;
6158 *ap->a_ncookies = 0;
6162 if (ap->a_ncookies == NULL)
6165 KASSERT(ap->a_cookies,
6166 ("NULL ap->a_cookies value with non-NULL ap->a_ncookies!"));
6168 *ap->a_cookies = realloc(*ap->a_cookies,
6169 (*ap->a_ncookies + 1) * sizeof(u_long), M_TEMP, M_WAITOK | M_ZERO);
6170 (*ap->a_cookies)[*ap->a_ncookies] = off;
6171 *ap->a_ncookies += 1;
6176 * The purpose of this routine is to remove granularity from accmode_t,
6177 * reducing it into standard unix access bits - VEXEC, VREAD, VWRITE,
6178 * VADMIN and VAPPEND.
6180 * If it returns 0, the caller is supposed to continue with the usual
6181 * access checks using 'accmode' as modified by this routine. If it
6182 * returns nonzero value, the caller is supposed to return that value
6185 * Note that after this routine runs, accmode may be zero.
6188 vfs_unixify_accmode(accmode_t *accmode)
6191 * There is no way to specify explicit "deny" rule using
6192 * file mode or POSIX.1e ACLs.
6194 if (*accmode & VEXPLICIT_DENY) {
6200 * None of these can be translated into usual access bits.
6201 * Also, the common case for NFSv4 ACLs is to not contain
6202 * either of these bits. Caller should check for VWRITE
6203 * on the containing directory instead.
6205 if (*accmode & (VDELETE_CHILD | VDELETE))
6208 if (*accmode & VADMIN_PERMS) {
6209 *accmode &= ~VADMIN_PERMS;
6214 * There is no way to deny VREAD_ATTRIBUTES, VREAD_ACL
6215 * or VSYNCHRONIZE using file mode or POSIX.1e ACL.
6217 *accmode &= ~(VSTAT_PERMS | VSYNCHRONIZE);
6223 * Clear out a doomed vnode (if any) and replace it with a new one as long
6224 * as the fs is not being unmounted. Return the root vnode to the caller.
6226 static int __noinline
6227 vfs_cache_root_fallback(struct mount *mp, int flags, struct vnode **vpp)
6233 if (mp->mnt_rootvnode != NULL) {
6235 vp = mp->mnt_rootvnode;
6237 if (!VN_IS_DOOMED(vp)) {
6240 error = vn_lock(vp, flags);
6249 * Clear the old one.
6251 mp->mnt_rootvnode = NULL;
6255 vfs_op_barrier_wait(mp);
6259 error = VFS_CACHEDROOT(mp, flags, vpp);
6262 if (mp->mnt_vfs_ops == 0) {
6264 if (mp->mnt_vfs_ops != 0) {
6268 if (mp->mnt_rootvnode == NULL) {
6270 mp->mnt_rootvnode = *vpp;
6272 if (mp->mnt_rootvnode != *vpp) {
6273 if (!VN_IS_DOOMED(mp->mnt_rootvnode)) {
6274 panic("%s: mismatch between vnode returned "
6275 " by VFS_CACHEDROOT and the one cached "
6277 __func__, *vpp, mp->mnt_rootvnode);
6287 vfs_cache_root(struct mount *mp, int flags, struct vnode **vpp)
6292 if (!vfs_op_thread_enter(mp))
6293 return (vfs_cache_root_fallback(mp, flags, vpp));
6294 vp = atomic_load_ptr(&mp->mnt_rootvnode);
6295 if (vp == NULL || VN_IS_DOOMED(vp)) {
6296 vfs_op_thread_exit(mp);
6297 return (vfs_cache_root_fallback(mp, flags, vpp));
6300 vfs_op_thread_exit(mp);
6301 error = vn_lock(vp, flags);
6304 return (vfs_cache_root_fallback(mp, flags, vpp));
6311 vfs_cache_root_clear(struct mount *mp)
6316 * ops > 0 guarantees there is nobody who can see this vnode
6318 MPASS(mp->mnt_vfs_ops > 0);
6319 vp = mp->mnt_rootvnode;
6321 vn_seqc_write_begin(vp);
6322 mp->mnt_rootvnode = NULL;
6327 vfs_cache_root_set(struct mount *mp, struct vnode *vp)
6330 MPASS(mp->mnt_vfs_ops > 0);
6332 mp->mnt_rootvnode = vp;
6336 * These are helper functions for filesystems to traverse all
6337 * their vnodes. See MNT_VNODE_FOREACH_ALL() in sys/mount.h.
6339 * This interface replaces MNT_VNODE_FOREACH.
6343 __mnt_vnode_next_all(struct vnode **mvp, struct mount *mp)
6348 kern_yield(PRI_USER);
6350 KASSERT((*mvp)->v_mount == mp, ("marker vnode mount list mismatch"));
6351 for (vp = TAILQ_NEXT(*mvp, v_nmntvnodes); vp != NULL;
6352 vp = TAILQ_NEXT(vp, v_nmntvnodes)) {
6353 /* Allow a racy peek at VIRF_DOOMED to save a lock acquisition. */
6354 if (vp->v_type == VMARKER || VN_IS_DOOMED(vp))
6357 if (VN_IS_DOOMED(vp)) {
6364 __mnt_vnode_markerfree_all(mvp, mp);
6365 /* MNT_IUNLOCK(mp); -- done in above function */
6366 mtx_assert(MNT_MTX(mp), MA_NOTOWNED);
6369 TAILQ_REMOVE(&mp->mnt_nvnodelist, *mvp, v_nmntvnodes);
6370 TAILQ_INSERT_AFTER(&mp->mnt_nvnodelist, vp, *mvp, v_nmntvnodes);
6376 __mnt_vnode_first_all(struct vnode **mvp, struct mount *mp)
6380 *mvp = vn_alloc_marker(mp);
6384 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) {
6385 /* Allow a racy peek at VIRF_DOOMED to save a lock acquisition. */
6386 if (vp->v_type == VMARKER || VN_IS_DOOMED(vp))
6389 if (VN_IS_DOOMED(vp)) {
6398 vn_free_marker(*mvp);
6402 TAILQ_INSERT_AFTER(&mp->mnt_nvnodelist, vp, *mvp, v_nmntvnodes);
6408 __mnt_vnode_markerfree_all(struct vnode **mvp, struct mount *mp)
6416 mtx_assert(MNT_MTX(mp), MA_OWNED);
6418 KASSERT((*mvp)->v_mount == mp, ("marker vnode mount list mismatch"));
6419 TAILQ_REMOVE(&mp->mnt_nvnodelist, *mvp, v_nmntvnodes);
6422 vn_free_marker(*mvp);
6427 * These are helper functions for filesystems to traverse their
6428 * lazy vnodes. See MNT_VNODE_FOREACH_LAZY() in sys/mount.h
6431 mnt_vnode_markerfree_lazy(struct vnode **mvp, struct mount *mp)
6434 KASSERT((*mvp)->v_mount == mp, ("marker vnode mount list mismatch"));
6439 vn_free_marker(*mvp);
6444 * Relock the mp mount vnode list lock with the vp vnode interlock in the
6445 * conventional lock order during mnt_vnode_next_lazy iteration.
6447 * On entry, the mount vnode list lock is held and the vnode interlock is not.
6448 * The list lock is dropped and reacquired. On success, both locks are held.
6449 * On failure, the mount vnode list lock is held but the vnode interlock is
6450 * not, and the procedure may have yielded.
6453 mnt_vnode_next_lazy_relock(struct vnode *mvp, struct mount *mp,
6457 VNASSERT(mvp->v_mount == mp && mvp->v_type == VMARKER &&
6458 TAILQ_NEXT(mvp, v_lazylist) != NULL, mvp,
6459 ("%s: bad marker", __func__));
6460 VNASSERT(vp->v_mount == mp && vp->v_type != VMARKER, vp,
6461 ("%s: inappropriate vnode", __func__));
6462 ASSERT_VI_UNLOCKED(vp, __func__);
6463 mtx_assert(&mp->mnt_listmtx, MA_OWNED);
6465 TAILQ_REMOVE(&mp->mnt_lazyvnodelist, mvp, v_lazylist);
6466 TAILQ_INSERT_BEFORE(vp, mvp, v_lazylist);
6469 * Note we may be racing against vdrop which transitioned the hold
6470 * count to 0 and now waits for the ->mnt_listmtx lock. This is fine,
6471 * if we are the only user after we get the interlock we will just
6475 mtx_unlock(&mp->mnt_listmtx);
6477 if (VN_IS_DOOMED(vp)) {
6478 VNPASS((vp->v_mflag & VMP_LAZYLIST) == 0, vp);
6481 VNPASS(vp->v_mflag & VMP_LAZYLIST, vp);
6483 * There is nothing to do if we are the last user.
6485 if (!refcount_release_if_not_last(&vp->v_holdcnt))
6487 mtx_lock(&mp->mnt_listmtx);
6492 mtx_lock(&mp->mnt_listmtx);
6496 static struct vnode *
6497 mnt_vnode_next_lazy(struct vnode **mvp, struct mount *mp, mnt_lazy_cb_t *cb,
6502 mtx_assert(&mp->mnt_listmtx, MA_OWNED);
6503 KASSERT((*mvp)->v_mount == mp, ("marker vnode mount list mismatch"));
6505 vp = TAILQ_NEXT(*mvp, v_lazylist);
6506 while (vp != NULL) {
6507 if (vp->v_type == VMARKER) {
6508 vp = TAILQ_NEXT(vp, v_lazylist);
6512 * See if we want to process the vnode. Note we may encounter a
6513 * long string of vnodes we don't care about and hog the list
6514 * as a result. Check for it and requeue the marker.
6516 VNPASS(!VN_IS_DOOMED(vp), vp);
6517 if (!cb(vp, cbarg)) {
6518 if (!should_yield()) {
6519 vp = TAILQ_NEXT(vp, v_lazylist);
6522 TAILQ_REMOVE(&mp->mnt_lazyvnodelist, *mvp,
6524 TAILQ_INSERT_AFTER(&mp->mnt_lazyvnodelist, vp, *mvp,
6526 mtx_unlock(&mp->mnt_listmtx);
6527 kern_yield(PRI_USER);
6528 mtx_lock(&mp->mnt_listmtx);
6532 * Try-lock because this is the wrong lock order.
6534 if (!VI_TRYLOCK(vp) &&
6535 !mnt_vnode_next_lazy_relock(*mvp, mp, vp))
6537 KASSERT(vp->v_type != VMARKER, ("locked marker %p", vp));
6538 KASSERT(vp->v_mount == mp || vp->v_mount == NULL,
6539 ("alien vnode on the lazy list %p %p", vp, mp));
6540 VNPASS(vp->v_mount == mp, vp);
6541 VNPASS(!VN_IS_DOOMED(vp), vp);
6544 TAILQ_REMOVE(&mp->mnt_lazyvnodelist, *mvp, v_lazylist);
6546 /* Check if we are done */
6548 mtx_unlock(&mp->mnt_listmtx);
6549 mnt_vnode_markerfree_lazy(mvp, mp);
6552 TAILQ_INSERT_AFTER(&mp->mnt_lazyvnodelist, vp, *mvp, v_lazylist);
6553 mtx_unlock(&mp->mnt_listmtx);
6554 ASSERT_VI_LOCKED(vp, "lazy iter");
6559 __mnt_vnode_next_lazy(struct vnode **mvp, struct mount *mp, mnt_lazy_cb_t *cb,
6564 kern_yield(PRI_USER);
6565 mtx_lock(&mp->mnt_listmtx);
6566 return (mnt_vnode_next_lazy(mvp, mp, cb, cbarg));
6570 __mnt_vnode_first_lazy(struct vnode **mvp, struct mount *mp, mnt_lazy_cb_t *cb,
6575 if (TAILQ_EMPTY(&mp->mnt_lazyvnodelist))
6578 *mvp = vn_alloc_marker(mp);
6583 mtx_lock(&mp->mnt_listmtx);
6584 vp = TAILQ_FIRST(&mp->mnt_lazyvnodelist);
6586 mtx_unlock(&mp->mnt_listmtx);
6587 mnt_vnode_markerfree_lazy(mvp, mp);
6590 TAILQ_INSERT_BEFORE(vp, *mvp, v_lazylist);
6591 return (mnt_vnode_next_lazy(mvp, mp, cb, cbarg));
6595 __mnt_vnode_markerfree_lazy(struct vnode **mvp, struct mount *mp)
6601 mtx_lock(&mp->mnt_listmtx);
6602 TAILQ_REMOVE(&mp->mnt_lazyvnodelist, *mvp, v_lazylist);
6603 mtx_unlock(&mp->mnt_listmtx);
6604 mnt_vnode_markerfree_lazy(mvp, mp);
6608 vn_dir_check_exec(struct vnode *vp, struct componentname *cnp)
6611 if ((cnp->cn_flags & NOEXECCHECK) != 0) {
6612 cnp->cn_flags &= ~NOEXECCHECK;
6616 return (VOP_ACCESS(vp, VEXEC, cnp->cn_cred, cnp->cn_thread));
6620 * Do not use this variant unless you have means other than the hold count
6621 * to prevent the vnode from getting freed.
6624 vn_seqc_write_begin_unheld_locked(struct vnode *vp)
6627 ASSERT_VI_LOCKED(vp, __func__);
6628 VNPASS(vp->v_seqc_users >= 0, vp);
6630 if (vp->v_seqc_users == 1)
6631 seqc_sleepable_write_begin(&vp->v_seqc);
6635 vn_seqc_write_begin_locked(struct vnode *vp)
6638 ASSERT_VI_LOCKED(vp, __func__);
6639 VNPASS(vp->v_holdcnt > 0, vp);
6640 vn_seqc_write_begin_unheld_locked(vp);
6644 vn_seqc_write_begin(struct vnode *vp)
6648 vn_seqc_write_begin_locked(vp);
6653 vn_seqc_write_begin_unheld(struct vnode *vp)
6657 vn_seqc_write_begin_unheld_locked(vp);
6662 vn_seqc_write_end_locked(struct vnode *vp)
6665 ASSERT_VI_LOCKED(vp, __func__);
6666 VNPASS(vp->v_seqc_users > 0, vp);
6668 if (vp->v_seqc_users == 0)
6669 seqc_sleepable_write_end(&vp->v_seqc);
6673 vn_seqc_write_end(struct vnode *vp)
6677 vn_seqc_write_end_locked(vp);