Initial import from FreeBSD RELENG_4:
[dragonfly.git] / sys / kern / vfs_subr.c
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1/*
2 * Copyright (c) 1989, 1993
3 * The Regents of the University of California. All rights reserved.
4 * (c) UNIX System Laboratories, Inc.
5 * All or some portions of this file are derived from material licensed
6 * to the University of California by American Telephone and Telegraph
7 * Co. or Unix System Laboratories, Inc. and are reproduced herein with
8 * the permission of UNIX System Laboratories, Inc.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 * 3. All advertising materials mentioning features or use of this software
19 * must display the following acknowledgement:
20 * This product includes software developed by the University of
21 * California, Berkeley and its contributors.
22 * 4. Neither the name of the University nor the names of its contributors
23 * may be used to endorse or promote products derived from this software
24 * without specific prior written permission.
25 *
26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36 * SUCH DAMAGE.
37 *
38 * @(#)vfs_subr.c 8.31 (Berkeley) 5/26/95
39 * $FreeBSD: src/sys/kern/vfs_subr.c,v 1.249.2.30 2003/04/04 20:35:57 tegge Exp $
40 */
41
42/*
43 * External virtual filesystem routines
44 */
45#include "opt_ddb.h"
46
47#include <sys/param.h>
48#include <sys/systm.h>
49#include <sys/buf.h>
50#include <sys/conf.h>
51#include <sys/dirent.h>
52#include <sys/domain.h>
53#include <sys/eventhandler.h>
54#include <sys/fcntl.h>
55#include <sys/kernel.h>
56#include <sys/kthread.h>
57#include <sys/malloc.h>
58#include <sys/mbuf.h>
59#include <sys/mount.h>
60#include <sys/namei.h>
61#include <sys/proc.h>
62#include <sys/reboot.h>
63#include <sys/socket.h>
64#include <sys/stat.h>
65#include <sys/sysctl.h>
66#include <sys/syslog.h>
67#include <sys/vmmeter.h>
68#include <sys/vnode.h>
69
70#include <machine/limits.h>
71
72#include <vm/vm.h>
73#include <vm/vm_object.h>
74#include <vm/vm_extern.h>
75#include <vm/pmap.h>
76#include <vm/vm_map.h>
77#include <vm/vm_page.h>
78#include <vm/vm_pager.h>
79#include <vm/vnode_pager.h>
80#include <vm/vm_zone.h>
81
82static MALLOC_DEFINE(M_NETADDR, "Export Host", "Export host address structure");
83
84static void insmntque __P((struct vnode *vp, struct mount *mp));
85static void vclean __P((struct vnode *vp, int flags, struct proc *p));
86static unsigned long numvnodes;
87static void vlruvp(struct vnode *vp);
88SYSCTL_INT(_debug, OID_AUTO, numvnodes, CTLFLAG_RD, &numvnodes, 0, "");
89
90enum vtype iftovt_tab[16] = {
91 VNON, VFIFO, VCHR, VNON, VDIR, VNON, VBLK, VNON,
92 VREG, VNON, VLNK, VNON, VSOCK, VNON, VNON, VBAD,
93};
94int vttoif_tab[9] = {
95 0, S_IFREG, S_IFDIR, S_IFBLK, S_IFCHR, S_IFLNK,
96 S_IFSOCK, S_IFIFO, S_IFMT,
97};
98
99static TAILQ_HEAD(freelst, vnode) vnode_free_list; /* vnode free list */
100
101static u_long wantfreevnodes = 25;
102SYSCTL_INT(_debug, OID_AUTO, wantfreevnodes, CTLFLAG_RW, &wantfreevnodes, 0, "");
103static u_long freevnodes = 0;
104SYSCTL_INT(_debug, OID_AUTO, freevnodes, CTLFLAG_RD, &freevnodes, 0, "");
105
106static int reassignbufcalls;
107SYSCTL_INT(_vfs, OID_AUTO, reassignbufcalls, CTLFLAG_RW, &reassignbufcalls, 0, "");
108static int reassignbufloops;
109SYSCTL_INT(_vfs, OID_AUTO, reassignbufloops, CTLFLAG_RW, &reassignbufloops, 0, "");
110static int reassignbufsortgood;
111SYSCTL_INT(_vfs, OID_AUTO, reassignbufsortgood, CTLFLAG_RW, &reassignbufsortgood, 0, "");
112static int reassignbufsortbad;
113SYSCTL_INT(_vfs, OID_AUTO, reassignbufsortbad, CTLFLAG_RW, &reassignbufsortbad, 0, "");
114static int reassignbufmethod = 1;
115SYSCTL_INT(_vfs, OID_AUTO, reassignbufmethod, CTLFLAG_RW, &reassignbufmethod, 0, "");
116static int nameileafonly = 0;
117SYSCTL_INT(_vfs, OID_AUTO, nameileafonly, CTLFLAG_RW, &nameileafonly, 0, "");
118
119#ifdef ENABLE_VFS_IOOPT
120int vfs_ioopt = 0;
121SYSCTL_INT(_vfs, OID_AUTO, ioopt, CTLFLAG_RW, &vfs_ioopt, 0, "");
122#endif
123
124struct mntlist mountlist = TAILQ_HEAD_INITIALIZER(mountlist); /* mounted fs */
125struct simplelock mountlist_slock;
126struct simplelock mntvnode_slock;
127int nfs_mount_type = -1;
128#ifndef NULL_SIMPLELOCKS
129static struct simplelock mntid_slock;
130static struct simplelock vnode_free_list_slock;
131static struct simplelock spechash_slock;
132#endif
133struct nfs_public nfs_pub; /* publicly exported FS */
134static vm_zone_t vnode_zone;
135
136/*
137 * The workitem queue.
138 */
139#define SYNCER_MAXDELAY 32
140static int syncer_maxdelay = SYNCER_MAXDELAY; /* maximum delay time */
141time_t syncdelay = 30; /* max time to delay syncing data */
142time_t filedelay = 30; /* time to delay syncing files */
143SYSCTL_INT(_kern, OID_AUTO, filedelay, CTLFLAG_RW, &filedelay, 0, "");
144time_t dirdelay = 29; /* time to delay syncing directories */
145SYSCTL_INT(_kern, OID_AUTO, dirdelay, CTLFLAG_RW, &dirdelay, 0, "");
146time_t metadelay = 28; /* time to delay syncing metadata */
147SYSCTL_INT(_kern, OID_AUTO, metadelay, CTLFLAG_RW, &metadelay, 0, "");
148static int rushjob; /* number of slots to run ASAP */
149static int stat_rush_requests; /* number of times I/O speeded up */
150SYSCTL_INT(_debug, OID_AUTO, rush_requests, CTLFLAG_RW, &stat_rush_requests, 0, "");
151
152static int syncer_delayno = 0;
153static long syncer_mask;
154LIST_HEAD(synclist, vnode);
155static struct synclist *syncer_workitem_pending;
156
157int desiredvnodes;
158SYSCTL_INT(_kern, KERN_MAXVNODES, maxvnodes, CTLFLAG_RW,
159 &desiredvnodes, 0, "Maximum number of vnodes");
160static int minvnodes;
161SYSCTL_INT(_kern, OID_AUTO, minvnodes, CTLFLAG_RW,
162 &minvnodes, 0, "Minimum number of vnodes");
163static int vnlru_nowhere = 0;
164SYSCTL_INT(_debug, OID_AUTO, vnlru_nowhere, CTLFLAG_RW, &vnlru_nowhere, 0,
165 "Number of times the vnlru process ran without success");
166
167static void vfs_free_addrlist __P((struct netexport *nep));
168static int vfs_free_netcred __P((struct radix_node *rn, void *w));
169static int vfs_hang_addrlist __P((struct mount *mp, struct netexport *nep,
170 struct export_args *argp));
171
172/*
173 * Initialize the vnode management data structures.
174 */
175void
176vntblinit()
177{
178
179 desiredvnodes = maxproc + cnt.v_page_count / 4;
180 minvnodes = desiredvnodes / 4;
181 simple_lock_init(&mntvnode_slock);
182 simple_lock_init(&mntid_slock);
183 simple_lock_init(&spechash_slock);
184 TAILQ_INIT(&vnode_free_list);
185 simple_lock_init(&vnode_free_list_slock);
186 vnode_zone = zinit("VNODE", sizeof (struct vnode), 0, 0, 5);
187 /*
188 * Initialize the filesystem syncer.
189 */
190 syncer_workitem_pending = hashinit(syncer_maxdelay, M_VNODE,
191 &syncer_mask);
192 syncer_maxdelay = syncer_mask + 1;
193}
194
195/*
196 * Mark a mount point as busy. Used to synchronize access and to delay
197 * unmounting. Interlock is not released on failure.
198 */
199int
200vfs_busy(mp, flags, interlkp, p)
201 struct mount *mp;
202 int flags;
203 struct simplelock *interlkp;
204 struct proc *p;
205{
206 int lkflags;
207
208 if (mp->mnt_kern_flag & MNTK_UNMOUNT) {
209 if (flags & LK_NOWAIT)
210 return (ENOENT);
211 mp->mnt_kern_flag |= MNTK_MWAIT;
212 if (interlkp) {
213 simple_unlock(interlkp);
214 }
215 /*
216 * Since all busy locks are shared except the exclusive
217 * lock granted when unmounting, the only place that a
218 * wakeup needs to be done is at the release of the
219 * exclusive lock at the end of dounmount.
220 */
221 tsleep((caddr_t)mp, PVFS, "vfs_busy", 0);
222 if (interlkp) {
223 simple_lock(interlkp);
224 }
225 return (ENOENT);
226 }
227 lkflags = LK_SHARED | LK_NOPAUSE;
228 if (interlkp)
229 lkflags |= LK_INTERLOCK;
230 if (lockmgr(&mp->mnt_lock, lkflags, interlkp, p))
231 panic("vfs_busy: unexpected lock failure");
232 return (0);
233}
234
235/*
236 * Free a busy filesystem.
237 */
238void
239vfs_unbusy(mp, p)
240 struct mount *mp;
241 struct proc *p;
242{
243
244 lockmgr(&mp->mnt_lock, LK_RELEASE, NULL, p);
245}
246
247/*
248 * Lookup a filesystem type, and if found allocate and initialize
249 * a mount structure for it.
250 *
251 * Devname is usually updated by mount(8) after booting.
252 */
253int
254vfs_rootmountalloc(fstypename, devname, mpp)
255 char *fstypename;
256 char *devname;
257 struct mount **mpp;
258{
259 struct proc *p = curproc; /* XXX */
260 struct vfsconf *vfsp;
261 struct mount *mp;
262
263 if (fstypename == NULL)
264 return (ENODEV);
265 for (vfsp = vfsconf; vfsp; vfsp = vfsp->vfc_next)
266 if (!strcmp(vfsp->vfc_name, fstypename))
267 break;
268 if (vfsp == NULL)
269 return (ENODEV);
270 mp = malloc((u_long)sizeof(struct mount), M_MOUNT, M_WAITOK);
271 bzero((char *)mp, (u_long)sizeof(struct mount));
272 lockinit(&mp->mnt_lock, PVFS, "vfslock", VLKTIMEOUT, LK_NOPAUSE);
273 (void)vfs_busy(mp, LK_NOWAIT, 0, p);
274 TAILQ_INIT(&mp->mnt_nvnodelist);
275 TAILQ_INIT(&mp->mnt_reservedvnlist);
276 mp->mnt_nvnodelistsize = 0;
277 mp->mnt_vfc = vfsp;
278 mp->mnt_op = vfsp->vfc_vfsops;
279 mp->mnt_flag = MNT_RDONLY;
280 mp->mnt_vnodecovered = NULLVP;
281 vfsp->vfc_refcount++;
282 mp->mnt_iosize_max = DFLTPHYS;
283 mp->mnt_stat.f_type = vfsp->vfc_typenum;
284 mp->mnt_flag |= vfsp->vfc_flags & MNT_VISFLAGMASK;
285 strncpy(mp->mnt_stat.f_fstypename, vfsp->vfc_name, MFSNAMELEN);
286 mp->mnt_stat.f_mntonname[0] = '/';
287 mp->mnt_stat.f_mntonname[1] = 0;
288 (void) copystr(devname, mp->mnt_stat.f_mntfromname, MNAMELEN - 1, 0);
289 *mpp = mp;
290 return (0);
291}
292
293/*
294 * Find an appropriate filesystem to use for the root. If a filesystem
295 * has not been preselected, walk through the list of known filesystems
296 * trying those that have mountroot routines, and try them until one
297 * works or we have tried them all.
298 */
299#ifdef notdef /* XXX JH */
300int
301lite2_vfs_mountroot()
302{
303 struct vfsconf *vfsp;
304 extern int (*lite2_mountroot) __P((void));
305 int error;
306
307 if (lite2_mountroot != NULL)
308 return ((*lite2_mountroot)());
309 for (vfsp = vfsconf; vfsp; vfsp = vfsp->vfc_next) {
310 if (vfsp->vfc_mountroot == NULL)
311 continue;
312 if ((error = (*vfsp->vfc_mountroot)()) == 0)
313 return (0);
314 printf("%s_mountroot failed: %d\n", vfsp->vfc_name, error);
315 }
316 return (ENODEV);
317}
318#endif
319
320/*
321 * Lookup a mount point by filesystem identifier.
322 */
323struct mount *
324vfs_getvfs(fsid)
325 fsid_t *fsid;
326{
327 register struct mount *mp;
328
329 simple_lock(&mountlist_slock);
330 TAILQ_FOREACH(mp, &mountlist, mnt_list) {
331 if (mp->mnt_stat.f_fsid.val[0] == fsid->val[0] &&
332 mp->mnt_stat.f_fsid.val[1] == fsid->val[1]) {
333 simple_unlock(&mountlist_slock);
334 return (mp);
335 }
336 }
337 simple_unlock(&mountlist_slock);
338 return ((struct mount *) 0);
339}
340
341/*
342 * Get a new unique fsid. Try to make its val[0] unique, since this value
343 * will be used to create fake device numbers for stat(). Also try (but
344 * not so hard) make its val[0] unique mod 2^16, since some emulators only
345 * support 16-bit device numbers. We end up with unique val[0]'s for the
346 * first 2^16 calls and unique val[0]'s mod 2^16 for the first 2^8 calls.
347 *
348 * Keep in mind that several mounts may be running in parallel. Starting
349 * the search one past where the previous search terminated is both a
350 * micro-optimization and a defense against returning the same fsid to
351 * different mounts.
352 */
353void
354vfs_getnewfsid(mp)
355 struct mount *mp;
356{
357 static u_int16_t mntid_base;
358 fsid_t tfsid;
359 int mtype;
360
361 simple_lock(&mntid_slock);
362 mtype = mp->mnt_vfc->vfc_typenum;
363 tfsid.val[1] = mtype;
364 mtype = (mtype & 0xFF) << 24;
365 for (;;) {
366 tfsid.val[0] = makeudev(255,
367 mtype | ((mntid_base & 0xFF00) << 8) | (mntid_base & 0xFF));
368 mntid_base++;
369 if (vfs_getvfs(&tfsid) == NULL)
370 break;
371 }
372 mp->mnt_stat.f_fsid.val[0] = tfsid.val[0];
373 mp->mnt_stat.f_fsid.val[1] = tfsid.val[1];
374 simple_unlock(&mntid_slock);
375}
376
377/*
378 * Knob to control the precision of file timestamps:
379 *
380 * 0 = seconds only; nanoseconds zeroed.
381 * 1 = seconds and nanoseconds, accurate within 1/HZ.
382 * 2 = seconds and nanoseconds, truncated to microseconds.
383 * >=3 = seconds and nanoseconds, maximum precision.
384 */
385enum { TSP_SEC, TSP_HZ, TSP_USEC, TSP_NSEC };
386
387static int timestamp_precision = TSP_SEC;
388SYSCTL_INT(_vfs, OID_AUTO, timestamp_precision, CTLFLAG_RW,
389 &timestamp_precision, 0, "");
390
391/*
392 * Get a current timestamp.
393 */
394void
395vfs_timestamp(tsp)
396 struct timespec *tsp;
397{
398 struct timeval tv;
399
400 switch (timestamp_precision) {
401 case TSP_SEC:
402 tsp->tv_sec = time_second;
403 tsp->tv_nsec = 0;
404 break;
405 case TSP_HZ:
406 getnanotime(tsp);
407 break;
408 case TSP_USEC:
409 microtime(&tv);
410 TIMEVAL_TO_TIMESPEC(&tv, tsp);
411 break;
412 case TSP_NSEC:
413 default:
414 nanotime(tsp);
415 break;
416 }
417}
418
419/*
420 * Set vnode attributes to VNOVAL
421 */
422void
423vattr_null(vap)
424 register struct vattr *vap;
425{
426
427 vap->va_type = VNON;
428 vap->va_size = VNOVAL;
429 vap->va_bytes = VNOVAL;
430 vap->va_mode = VNOVAL;
431 vap->va_nlink = VNOVAL;
432 vap->va_uid = VNOVAL;
433 vap->va_gid = VNOVAL;
434 vap->va_fsid = VNOVAL;
435 vap->va_fileid = VNOVAL;
436 vap->va_blocksize = VNOVAL;
437 vap->va_rdev = VNOVAL;
438 vap->va_atime.tv_sec = VNOVAL;
439 vap->va_atime.tv_nsec = VNOVAL;
440 vap->va_mtime.tv_sec = VNOVAL;
441 vap->va_mtime.tv_nsec = VNOVAL;
442 vap->va_ctime.tv_sec = VNOVAL;
443 vap->va_ctime.tv_nsec = VNOVAL;
444 vap->va_flags = VNOVAL;
445 vap->va_gen = VNOVAL;
446 vap->va_vaflags = 0;
447}
448
449/*
450 * This routine is called when we have too many vnodes. It attempts
451 * to free <count> vnodes and will potentially free vnodes that still
452 * have VM backing store (VM backing store is typically the cause
453 * of a vnode blowout so we want to do this). Therefore, this operation
454 * is not considered cheap.
455 *
456 * A number of conditions may prevent a vnode from being reclaimed.
457 * the buffer cache may have references on the vnode, a directory
458 * vnode may still have references due to the namei cache representing
459 * underlying files, or the vnode may be in active use. It is not
460 * desireable to reuse such vnodes. These conditions may cause the
461 * number of vnodes to reach some minimum value regardless of what
462 * you set kern.maxvnodes to. Do not set kern.maxvnodes too low.
463 */
464static int
465vlrureclaim(struct mount *mp)
466{
467 struct vnode *vp;
468 int done;
469 int trigger;
470 int usevnodes;
471 int count;
472
473 /*
474 * Calculate the trigger point, don't allow user
475 * screwups to blow us up. This prevents us from
476 * recycling vnodes with lots of resident pages. We
477 * aren't trying to free memory, we are trying to
478 * free vnodes.
479 */
480 usevnodes = desiredvnodes;
481 if (usevnodes <= 0)
482 usevnodes = 1;
483 trigger = cnt.v_page_count * 2 / usevnodes;
484
485 done = 0;
486 simple_lock(&mntvnode_slock);
487 count = mp->mnt_nvnodelistsize / 10 + 1;
488 while (count && (vp = TAILQ_FIRST(&mp->mnt_nvnodelist)) != NULL) {
489 TAILQ_REMOVE(&mp->mnt_nvnodelist, vp, v_nmntvnodes);
490 TAILQ_INSERT_TAIL(&mp->mnt_nvnodelist, vp, v_nmntvnodes);
491
492 if (vp->v_type != VNON &&
493 vp->v_type != VBAD &&
494 VMIGHTFREE(vp) && /* critical path opt */
495 (vp->v_object == NULL || vp->v_object->resident_page_count < trigger) &&
496 simple_lock_try(&vp->v_interlock)
497 ) {
498 simple_unlock(&mntvnode_slock);
499 if (VMIGHTFREE(vp)) {
500 vgonel(vp, curproc);
501 done++;
502 } else {
503 simple_unlock(&vp->v_interlock);
504 }
505 simple_lock(&mntvnode_slock);
506 }
507 --count;
508 }
509 simple_unlock(&mntvnode_slock);
510 return done;
511}
512
513/*
514 * Attempt to recycle vnodes in a context that is always safe to block.
515 * Calling vlrurecycle() from the bowels of file system code has some
516 * interesting deadlock problems.
517 */
518static struct proc *vnlruproc;
519static int vnlruproc_sig;
520
521static void
522vnlru_proc(void)
523{
524 struct mount *mp, *nmp;
525 int s;
526 int done;
527 struct proc *p = vnlruproc;
528
529 EVENTHANDLER_REGISTER(shutdown_pre_sync, shutdown_kproc, p,
530 SHUTDOWN_PRI_FIRST);
531
532 s = splbio();
533 for (;;) {
534 kproc_suspend_loop(p);
535 if (numvnodes - freevnodes <= desiredvnodes * 9 / 10) {
536 vnlruproc_sig = 0;
537 wakeup(&vnlruproc_sig);
538 tsleep(vnlruproc, PVFS, "vlruwt", hz);
539 continue;
540 }
541 done = 0;
542 simple_lock(&mountlist_slock);
543 for (mp = TAILQ_FIRST(&mountlist); mp != NULL; mp = nmp) {
544 if (vfs_busy(mp, LK_NOWAIT, &mountlist_slock, p)) {
545 nmp = TAILQ_NEXT(mp, mnt_list);
546 continue;
547 }
548 done += vlrureclaim(mp);
549 simple_lock(&mountlist_slock);
550 nmp = TAILQ_NEXT(mp, mnt_list);
551 vfs_unbusy(mp, p);
552 }
553 simple_unlock(&mountlist_slock);
554 if (done == 0) {
555 vnlru_nowhere++;
556 tsleep(vnlruproc, PPAUSE, "vlrup", hz * 3);
557 }
558 }
559 splx(s);
560}
561
562static struct kproc_desc vnlru_kp = {
563 "vnlru",
564 vnlru_proc,
565 &vnlruproc
566};
567SYSINIT(vnlru, SI_SUB_KTHREAD_UPDATE, SI_ORDER_FIRST, kproc_start, &vnlru_kp)
568
569/*
570 * Routines having to do with the management of the vnode table.
571 */
572extern vop_t **dead_vnodeop_p;
573
574/*
575 * Return the next vnode from the free list.
576 */
577int
578getnewvnode(tag, mp, vops, vpp)
579 enum vtagtype tag;
580 struct mount *mp;
581 vop_t **vops;
582 struct vnode **vpp;
583{
584 int s;
585 struct proc *p = curproc; /* XXX */
586 struct vnode *vp = NULL;
587 vm_object_t object;
588
589 s = splbio();
590
591 /*
592 * Try to reuse vnodes if we hit the max. This situation only
593 * occurs in certain large-memory (2G+) situations. We cannot
594 * attempt to directly reclaim vnodes due to nasty recursion
595 * problems.
596 */
597 while (numvnodes - freevnodes > desiredvnodes) {
598 if (vnlruproc_sig == 0) {
599 vnlruproc_sig = 1; /* avoid unnecessary wakeups */
600 wakeup(vnlruproc);
601 }
602 tsleep(&vnlruproc_sig, PVFS, "vlruwk", hz);
603 }
604
605
606 /*
607 * Attempt to reuse a vnode already on the free list, allocating
608 * a new vnode if we can't find one or if we have not reached a
609 * good minimum for good LRU performance.
610 */
611 simple_lock(&vnode_free_list_slock);
612 if (freevnodes >= wantfreevnodes && numvnodes >= minvnodes) {
613 int count;
614
615 for (count = 0; count < freevnodes; count++) {
616 vp = TAILQ_FIRST(&vnode_free_list);
617 if (vp == NULL || vp->v_usecount)
618 panic("getnewvnode: free vnode isn't");
619
620 TAILQ_REMOVE(&vnode_free_list, vp, v_freelist);
621 if ((VOP_GETVOBJECT(vp, &object) == 0 &&
622 (object->resident_page_count || object->ref_count)) ||
623 !simple_lock_try(&vp->v_interlock)) {
624 TAILQ_INSERT_TAIL(&vnode_free_list, vp, v_freelist);
625 vp = NULL;
626 continue;
627 }
628 if (LIST_FIRST(&vp->v_cache_src)) {
629 /*
630 * note: nameileafonly sysctl is temporary,
631 * for debugging only, and will eventually be
632 * removed.
633 */
634 if (nameileafonly > 0) {
635 /*
636 * Do not reuse namei-cached directory
637 * vnodes that have cached
638 * subdirectories.
639 */
640 if (cache_leaf_test(vp) < 0) {
641 simple_unlock(&vp->v_interlock);
642 TAILQ_INSERT_TAIL(&vnode_free_list, vp, v_freelist);
643 vp = NULL;
644 continue;
645 }
646 } else if (nameileafonly < 0 ||
647 vmiodirenable == 0) {
648 /*
649 * Do not reuse namei-cached directory
650 * vnodes if nameileafonly is -1 or
651 * if VMIO backing for directories is
652 * turned off (otherwise we reuse them
653 * too quickly).
654 */
655 simple_unlock(&vp->v_interlock);
656 TAILQ_INSERT_TAIL(&vnode_free_list, vp, v_freelist);
657 vp = NULL;
658 continue;
659 }
660 }
661 break;
662 }
663 }
664
665 if (vp) {
666 vp->v_flag |= VDOOMED;
667 vp->v_flag &= ~VFREE;
668 freevnodes--;
669 simple_unlock(&vnode_free_list_slock);
670 cache_purge(vp);
671 vp->v_lease = NULL;
672 if (vp->v_type != VBAD) {
673 vgonel(vp, p);
674 } else {
675 simple_unlock(&vp->v_interlock);
676 }
677
678#ifdef INVARIANTS
679 {
680 int s;
681
682 if (vp->v_data)
683 panic("cleaned vnode isn't");
684 s = splbio();
685 if (vp->v_numoutput)
686 panic("Clean vnode has pending I/O's");
687 splx(s);
688 }
689#endif
690 vp->v_flag = 0;
691 vp->v_lastw = 0;
692 vp->v_lasta = 0;
693 vp->v_cstart = 0;
694 vp->v_clen = 0;
695 vp->v_socket = 0;
696 vp->v_writecount = 0; /* XXX */
697 } else {
698 simple_unlock(&vnode_free_list_slock);
699 vp = (struct vnode *) zalloc(vnode_zone);
700 bzero((char *) vp, sizeof *vp);
701 simple_lock_init(&vp->v_interlock);
702 vp->v_dd = vp;
703 cache_purge(vp);
704 LIST_INIT(&vp->v_cache_src);
705 TAILQ_INIT(&vp->v_cache_dst);
706 numvnodes++;
707 }
708
709 TAILQ_INIT(&vp->v_cleanblkhd);
710 TAILQ_INIT(&vp->v_dirtyblkhd);
711 vp->v_type = VNON;
712 vp->v_tag = tag;
713 vp->v_op = vops;
714 insmntque(vp, mp);
715 *vpp = vp;
716 vp->v_usecount = 1;
717 vp->v_data = 0;
718 splx(s);
719
720 vfs_object_create(vp, p, p->p_ucred);
721 return (0);
722}
723
724/*
725 * Move a vnode from one mount queue to another.
726 */
727static void
728insmntque(vp, mp)
729 register struct vnode *vp;
730 register struct mount *mp;
731{
732
733 simple_lock(&mntvnode_slock);
734 /*
735 * Delete from old mount point vnode list, if on one.
736 */
737 if (vp->v_mount != NULL) {
738 KASSERT(vp->v_mount->mnt_nvnodelistsize > 0,
739 ("bad mount point vnode list size"));
740 TAILQ_REMOVE(&vp->v_mount->mnt_nvnodelist, vp, v_nmntvnodes);
741 vp->v_mount->mnt_nvnodelistsize--;
742 }
743 /*
744 * Insert into list of vnodes for the new mount point, if available.
745 */
746 if ((vp->v_mount = mp) == NULL) {
747 simple_unlock(&mntvnode_slock);
748 return;
749 }
750 TAILQ_INSERT_TAIL(&mp->mnt_nvnodelist, vp, v_nmntvnodes);
751 mp->mnt_nvnodelistsize++;
752 simple_unlock(&mntvnode_slock);
753}
754
755/*
756 * Update outstanding I/O count and do wakeup if requested.
757 */
758void
759vwakeup(bp)
760 register struct buf *bp;
761{
762 register struct vnode *vp;
763
764 bp->b_flags &= ~B_WRITEINPROG;
765 if ((vp = bp->b_vp)) {
766 vp->v_numoutput--;
767 if (vp->v_numoutput < 0)
768 panic("vwakeup: neg numoutput");
769 if ((vp->v_numoutput == 0) && (vp->v_flag & VBWAIT)) {
770 vp->v_flag &= ~VBWAIT;
771 wakeup((caddr_t) &vp->v_numoutput);
772 }
773 }
774}
775
776/*
777 * Flush out and invalidate all buffers associated with a vnode.
778 * Called with the underlying object locked.
779 */
780int
781vinvalbuf(vp, flags, cred, p, slpflag, slptimeo)
782 register struct vnode *vp;
783 int flags;
784 struct ucred *cred;
785 struct proc *p;
786 int slpflag, slptimeo;
787{
788 register struct buf *bp;
789 struct buf *nbp, *blist;
790 int s, error;
791 vm_object_t object;
792
793 if (flags & V_SAVE) {
794 s = splbio();
795 while (vp->v_numoutput) {
796 vp->v_flag |= VBWAIT;
797 error = tsleep((caddr_t)&vp->v_numoutput,
798 slpflag | (PRIBIO + 1), "vinvlbuf", slptimeo);
799 if (error) {
800 splx(s);
801 return (error);
802 }
803 }
804 if (!TAILQ_EMPTY(&vp->v_dirtyblkhd)) {
805 splx(s);
806 if ((error = VOP_FSYNC(vp, cred, MNT_WAIT, p)) != 0)
807 return (error);
808 s = splbio();
809 if (vp->v_numoutput > 0 ||
810 !TAILQ_EMPTY(&vp->v_dirtyblkhd))
811 panic("vinvalbuf: dirty bufs");
812 }
813 splx(s);
814 }
815 s = splbio();
816 for (;;) {
817 blist = TAILQ_FIRST(&vp->v_cleanblkhd);
818 if (!blist)
819 blist = TAILQ_FIRST(&vp->v_dirtyblkhd);
820 if (!blist)
821 break;
822
823 for (bp = blist; bp; bp = nbp) {
824 nbp = TAILQ_NEXT(bp, b_vnbufs);
825 if (BUF_LOCK(bp, LK_EXCLUSIVE | LK_NOWAIT)) {
826 error = BUF_TIMELOCK(bp,
827 LK_EXCLUSIVE | LK_SLEEPFAIL,
828 "vinvalbuf", slpflag, slptimeo);
829 if (error == ENOLCK)
830 break;
831 splx(s);
832 return (error);
833 }
834 /*
835 * XXX Since there are no node locks for NFS, I
836 * believe there is a slight chance that a delayed
837 * write will occur while sleeping just above, so
838 * check for it. Note that vfs_bio_awrite expects
839 * buffers to reside on a queue, while VOP_BWRITE and
840 * brelse do not.
841 */
842 if (((bp->b_flags & (B_DELWRI | B_INVAL)) == B_DELWRI) &&
843 (flags & V_SAVE)) {
844
845 if (bp->b_vp == vp) {
846 if (bp->b_flags & B_CLUSTEROK) {
847 BUF_UNLOCK(bp);
848 vfs_bio_awrite(bp);
849 } else {
850 bremfree(bp);
851 bp->b_flags |= B_ASYNC;
852 VOP_BWRITE(bp->b_vp, bp);
853 }
854 } else {
855 bremfree(bp);
856 (void) VOP_BWRITE(bp->b_vp, bp);
857 }
858 break;
859 }
860 bremfree(bp);
861 bp->b_flags |= (B_INVAL | B_NOCACHE | B_RELBUF);
862 bp->b_flags &= ~B_ASYNC;
863 brelse(bp);
864 }
865 }
866
867 /*
868 * Wait for I/O to complete. XXX needs cleaning up. The vnode can
869 * have write I/O in-progress but if there is a VM object then the
870 * VM object can also have read-I/O in-progress.
871 */
872 do {
873 while (vp->v_numoutput > 0) {
874 vp->v_flag |= VBWAIT;
875 tsleep(&vp->v_numoutput, PVM, "vnvlbv", 0);
876 }
877 if (VOP_GETVOBJECT(vp, &object) == 0) {
878 while (object->paging_in_progress)
879 vm_object_pip_sleep(object, "vnvlbx");
880 }
881 } while (vp->v_numoutput > 0);
882
883 splx(s);
884
885 /*
886 * Destroy the copy in the VM cache, too.
887 */
888 simple_lock(&vp->v_interlock);
889 if (VOP_GETVOBJECT(vp, &object) == 0) {
890 vm_object_page_remove(object, 0, 0,
891 (flags & V_SAVE) ? TRUE : FALSE);
892 }
893 simple_unlock(&vp->v_interlock);
894
895 if (!TAILQ_EMPTY(&vp->v_dirtyblkhd) || !TAILQ_EMPTY(&vp->v_cleanblkhd))
896 panic("vinvalbuf: flush failed");
897 return (0);
898}
899
900/*
901 * Truncate a file's buffer and pages to a specified length. This
902 * is in lieu of the old vinvalbuf mechanism, which performed unneeded
903 * sync activity.
904 */
905int
906vtruncbuf(vp, cred, p, length, blksize)
907 register struct vnode *vp;
908 struct ucred *cred;
909 struct proc *p;
910 off_t length;
911 int blksize;
912{
913 register struct buf *bp;
914 struct buf *nbp;
915 int s, anyfreed;
916 int trunclbn;
917
918 /*
919 * Round up to the *next* lbn.
920 */
921 trunclbn = (length + blksize - 1) / blksize;
922
923 s = splbio();
924restart:
925 anyfreed = 1;
926 for (;anyfreed;) {
927 anyfreed = 0;
928 for (bp = TAILQ_FIRST(&vp->v_cleanblkhd); bp; bp = nbp) {
929 nbp = TAILQ_NEXT(bp, b_vnbufs);
930 if (bp->b_lblkno >= trunclbn) {
931 if (BUF_LOCK(bp, LK_EXCLUSIVE | LK_NOWAIT)) {
932 BUF_LOCK(bp, LK_EXCLUSIVE|LK_SLEEPFAIL);
933 goto restart;
934 } else {
935 bremfree(bp);
936 bp->b_flags |= (B_INVAL | B_RELBUF);
937 bp->b_flags &= ~B_ASYNC;
938 brelse(bp);
939 anyfreed = 1;
940 }
941 if (nbp &&
942 (((nbp->b_xflags & BX_VNCLEAN) == 0) ||
943 (nbp->b_vp != vp) ||
944 (nbp->b_flags & B_DELWRI))) {
945 goto restart;
946 }
947 }
948 }
949
950 for (bp = TAILQ_FIRST(&vp->v_dirtyblkhd); bp; bp = nbp) {
951 nbp = TAILQ_NEXT(bp, b_vnbufs);
952 if (bp->b_lblkno >= trunclbn) {
953 if (BUF_LOCK(bp, LK_EXCLUSIVE | LK_NOWAIT)) {
954 BUF_LOCK(bp, LK_EXCLUSIVE|LK_SLEEPFAIL);
955 goto restart;
956 } else {
957 bremfree(bp);
958 bp->b_flags |= (B_INVAL | B_RELBUF);
959 bp->b_flags &= ~B_ASYNC;
960 brelse(bp);
961 anyfreed = 1;
962 }
963 if (nbp &&
964 (((nbp->b_xflags & BX_VNDIRTY) == 0) ||
965 (nbp->b_vp != vp) ||
966 (nbp->b_flags & B_DELWRI) == 0)) {
967 goto restart;
968 }
969 }
970 }
971 }
972
973 if (length > 0) {
974restartsync:
975 for (bp = TAILQ_FIRST(&vp->v_dirtyblkhd); bp; bp = nbp) {
976 nbp = TAILQ_NEXT(bp, b_vnbufs);
977 if ((bp->b_flags & B_DELWRI) && (bp->b_lblkno < 0)) {
978 if (BUF_LOCK(bp, LK_EXCLUSIVE | LK_NOWAIT)) {
979 BUF_LOCK(bp, LK_EXCLUSIVE|LK_SLEEPFAIL);
980 goto restart;
981 } else {
982 bremfree(bp);
983 if (bp->b_vp == vp) {
984 bp->b_flags |= B_ASYNC;
985 } else {
986 bp->b_flags &= ~B_ASYNC;
987 }
988 VOP_BWRITE(bp->b_vp, bp);
989 }
990 goto restartsync;
991 }
992
993 }
994 }
995
996 while (vp->v_numoutput > 0) {
997 vp->v_flag |= VBWAIT;
998 tsleep(&vp->v_numoutput, PVM, "vbtrunc", 0);
999 }
1000
1001 splx(s);
1002
1003 vnode_pager_setsize(vp, length);
1004
1005 return (0);
1006}
1007
1008/*
1009 * Associate a buffer with a vnode.
1010 */
1011void
1012bgetvp(vp, bp)
1013 register struct vnode *vp;
1014 register struct buf *bp;
1015{
1016 int s;
1017
1018 KASSERT(bp->b_vp == NULL, ("bgetvp: not free"));
1019
1020 vhold(vp);
1021 bp->b_vp = vp;
1022 bp->b_dev = vn_todev(vp);
1023 /*
1024 * Insert onto list for new vnode.
1025 */
1026 s = splbio();
1027 bp->b_xflags |= BX_VNCLEAN;
1028 bp->b_xflags &= ~BX_VNDIRTY;
1029 TAILQ_INSERT_TAIL(&vp->v_cleanblkhd, bp, b_vnbufs);
1030 splx(s);
1031}
1032
1033/*
1034 * Disassociate a buffer from a vnode.
1035 */
1036void
1037brelvp(bp)
1038 register struct buf *bp;
1039{
1040 struct vnode *vp;
1041 struct buflists *listheadp;
1042 int s;
1043
1044 KASSERT(bp->b_vp != NULL, ("brelvp: NULL"));
1045
1046 /*
1047 * Delete from old vnode list, if on one.
1048 */
1049 vp = bp->b_vp;
1050 s = splbio();
1051 if (bp->b_xflags & (BX_VNDIRTY | BX_VNCLEAN)) {
1052 if (bp->b_xflags & BX_VNDIRTY)
1053 listheadp = &vp->v_dirtyblkhd;
1054 else
1055 listheadp = &vp->v_cleanblkhd;
1056 TAILQ_REMOVE(listheadp, bp, b_vnbufs);
1057 bp->b_xflags &= ~(BX_VNDIRTY | BX_VNCLEAN);
1058 }
1059 if ((vp->v_flag & VONWORKLST) && TAILQ_EMPTY(&vp->v_dirtyblkhd)) {
1060 vp->v_flag &= ~VONWORKLST;
1061 LIST_REMOVE(vp, v_synclist);
1062 }
1063 splx(s);
1064 bp->b_vp = (struct vnode *) 0;
1065 vdrop(vp);
1066}
1067
1068/*
1069 * The workitem queue.
1070 *
1071 * It is useful to delay writes of file data and filesystem metadata
1072 * for tens of seconds so that quickly created and deleted files need
1073 * not waste disk bandwidth being created and removed. To realize this,
1074 * we append vnodes to a "workitem" queue. When running with a soft
1075 * updates implementation, most pending metadata dependencies should
1076 * not wait for more than a few seconds. Thus, mounted on block devices
1077 * are delayed only about a half the time that file data is delayed.
1078 * Similarly, directory updates are more critical, so are only delayed
1079 * about a third the time that file data is delayed. Thus, there are
1080 * SYNCER_MAXDELAY queues that are processed round-robin at a rate of
1081 * one each second (driven off the filesystem syncer process). The
1082 * syncer_delayno variable indicates the next queue that is to be processed.
1083 * Items that need to be processed soon are placed in this queue:
1084 *
1085 * syncer_workitem_pending[syncer_delayno]
1086 *
1087 * A delay of fifteen seconds is done by placing the request fifteen
1088 * entries later in the queue:
1089 *
1090 * syncer_workitem_pending[(syncer_delayno + 15) & syncer_mask]
1091 *
1092 */
1093
1094/*
1095 * Add an item to the syncer work queue.
1096 */
1097static void
1098vn_syncer_add_to_worklist(struct vnode *vp, int delay)
1099{
1100 int s, slot;
1101
1102 s = splbio();
1103
1104 if (vp->v_flag & VONWORKLST) {
1105 LIST_REMOVE(vp, v_synclist);
1106 }
1107
1108 if (delay > syncer_maxdelay - 2)
1109 delay = syncer_maxdelay - 2;
1110 slot = (syncer_delayno + delay) & syncer_mask;
1111
1112 LIST_INSERT_HEAD(&syncer_workitem_pending[slot], vp, v_synclist);
1113 vp->v_flag |= VONWORKLST;
1114 splx(s);
1115}
1116
1117struct proc *updateproc;
1118static void sched_sync __P((void));
1119static struct kproc_desc up_kp = {
1120 "syncer",
1121 sched_sync,
1122 &updateproc
1123};
1124SYSINIT(syncer, SI_SUB_KTHREAD_UPDATE, SI_ORDER_FIRST, kproc_start, &up_kp)
1125
1126/*
1127 * System filesystem synchronizer daemon.
1128 */
1129void
1130sched_sync(void)
1131{
1132 struct synclist *slp;
1133 struct vnode *vp;
1134 long starttime;
1135 int s;
1136 struct proc *p = updateproc;
1137
1138 EVENTHANDLER_REGISTER(shutdown_pre_sync, shutdown_kproc, p,
1139 SHUTDOWN_PRI_LAST);
1140
1141 for (;;) {
1142 kproc_suspend_loop(p);
1143
1144 starttime = time_second;
1145
1146 /*
1147 * Push files whose dirty time has expired. Be careful
1148 * of interrupt race on slp queue.
1149 */
1150 s = splbio();
1151 slp = &syncer_workitem_pending[syncer_delayno];
1152 syncer_delayno += 1;
1153 if (syncer_delayno == syncer_maxdelay)
1154 syncer_delayno = 0;
1155 splx(s);
1156
1157 while ((vp = LIST_FIRST(slp)) != NULL) {
1158 if (VOP_ISLOCKED(vp, NULL) == 0) {
1159 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, p);
1160 (void) VOP_FSYNC(vp, p->p_ucred, MNT_LAZY, p);
1161 VOP_UNLOCK(vp, 0, p);
1162 }
1163 s = splbio();
1164 if (LIST_FIRST(slp) == vp) {
1165 /*
1166 * Note: v_tag VT_VFS vps can remain on the
1167 * worklist too with no dirty blocks, but
1168 * since sync_fsync() moves it to a different
1169 * slot we are safe.
1170 */
1171 if (TAILQ_EMPTY(&vp->v_dirtyblkhd) &&
1172 !vn_isdisk(vp, NULL))
1173 panic("sched_sync: fsync failed vp %p tag %d", vp, vp->v_tag);
1174 /*
1175 * Put us back on the worklist. The worklist
1176 * routine will remove us from our current
1177 * position and then add us back in at a later
1178 * position.
1179 */
1180 vn_syncer_add_to_worklist(vp, syncdelay);
1181 }
1182 splx(s);
1183 }
1184
1185 /*
1186 * Do soft update processing.
1187 */
1188 if (bioops.io_sync)
1189 (*bioops.io_sync)(NULL);
1190
1191 /*
1192 * The variable rushjob allows the kernel to speed up the
1193 * processing of the filesystem syncer process. A rushjob
1194 * value of N tells the filesystem syncer to process the next
1195 * N seconds worth of work on its queue ASAP. Currently rushjob
1196 * is used by the soft update code to speed up the filesystem
1197 * syncer process when the incore state is getting so far
1198 * ahead of the disk that the kernel memory pool is being
1199 * threatened with exhaustion.
1200 */
1201 if (rushjob > 0) {
1202 rushjob -= 1;
1203 continue;
1204 }
1205 /*
1206 * If it has taken us less than a second to process the
1207 * current work, then wait. Otherwise start right over
1208 * again. We can still lose time if any single round
1209 * takes more than two seconds, but it does not really
1210 * matter as we are just trying to generally pace the
1211 * filesystem activity.
1212 */
1213 if (time_second == starttime)
1214 tsleep(&lbolt, PPAUSE, "syncer", 0);
1215 }
1216}
1217
1218/*
1219 * Request the syncer daemon to speed up its work.
1220 * We never push it to speed up more than half of its
1221 * normal turn time, otherwise it could take over the cpu.
1222 */
1223int
1224speedup_syncer()
1225{
1226 int s;
1227
1228 s = splhigh();
1229 if (updateproc->p_wchan == &lbolt)
1230 setrunnable(updateproc);
1231 splx(s);
1232 if (rushjob < syncdelay / 2) {
1233 rushjob += 1;
1234 stat_rush_requests += 1;
1235 return (1);
1236 }
1237 return(0);
1238}
1239
1240/*
1241 * Associate a p-buffer with a vnode.
1242 *
1243 * Also sets B_PAGING flag to indicate that vnode is not fully associated
1244 * with the buffer. i.e. the bp has not been linked into the vnode or
1245 * ref-counted.
1246 */
1247void
1248pbgetvp(vp, bp)
1249 register struct vnode *vp;
1250 register struct buf *bp;
1251{
1252
1253 KASSERT(bp->b_vp == NULL, ("pbgetvp: not free"));
1254
1255 bp->b_vp = vp;
1256 bp->b_flags |= B_PAGING;
1257 bp->b_dev = vn_todev(vp);
1258}
1259
1260/*
1261 * Disassociate a p-buffer from a vnode.
1262 */
1263void
1264pbrelvp(bp)
1265 register struct buf *bp;
1266{
1267
1268 KASSERT(bp->b_vp != NULL, ("pbrelvp: NULL"));
1269
1270 /* XXX REMOVE ME */
1271 if (TAILQ_NEXT(bp, b_vnbufs) != NULL) {
1272 panic(
1273 "relpbuf(): b_vp was probably reassignbuf()d %p %x",
1274 bp,
1275 (int)bp->b_flags
1276 );
1277 }
1278 bp->b_vp = (struct vnode *) 0;
1279 bp->b_flags &= ~B_PAGING;
1280}
1281
1282void
1283pbreassignbuf(bp, newvp)
1284 struct buf *bp;
1285 struct vnode *newvp;
1286{
1287 if ((bp->b_flags & B_PAGING) == 0) {
1288 panic(
1289 "pbreassignbuf() on non phys bp %p",
1290 bp
1291 );
1292 }
1293 bp->b_vp = newvp;
1294}
1295
1296/*
1297 * Reassign a buffer from one vnode to another.
1298 * Used to assign file specific control information
1299 * (indirect blocks) to the vnode to which they belong.
1300 */
1301void
1302reassignbuf(bp, newvp)
1303 register struct buf *bp;
1304 register struct vnode *newvp;
1305{
1306 struct buflists *listheadp;
1307 int delay;
1308 int s;
1309
1310 if (newvp == NULL) {
1311 printf("reassignbuf: NULL");
1312 return;
1313 }
1314 ++reassignbufcalls;
1315
1316 /*
1317 * B_PAGING flagged buffers cannot be reassigned because their vp
1318 * is not fully linked in.
1319 */
1320 if (bp->b_flags & B_PAGING)
1321 panic("cannot reassign paging buffer");
1322
1323 s = splbio();
1324 /*
1325 * Delete from old vnode list, if on one.
1326 */
1327 if (bp->b_xflags & (BX_VNDIRTY | BX_VNCLEAN)) {
1328 if (bp->b_xflags & BX_VNDIRTY)
1329 listheadp = &bp->b_vp->v_dirtyblkhd;
1330 else
1331 listheadp = &bp->b_vp->v_cleanblkhd;
1332 TAILQ_REMOVE(listheadp, bp, b_vnbufs);
1333 bp->b_xflags &= ~(BX_VNDIRTY | BX_VNCLEAN);
1334 if (bp->b_vp != newvp) {
1335 vdrop(bp->b_vp);
1336 bp->b_vp = NULL; /* for clarification */
1337 }
1338 }
1339 /*
1340 * If dirty, put on list of dirty buffers; otherwise insert onto list
1341 * of clean buffers.
1342 */
1343 if (bp->b_flags & B_DELWRI) {
1344 struct buf *tbp;
1345
1346 listheadp = &newvp->v_dirtyblkhd;
1347 if ((newvp->v_flag & VONWORKLST) == 0) {
1348 switch (newvp->v_type) {
1349 case VDIR:
1350 delay = dirdelay;
1351 break;
1352 case VCHR:
1353 case VBLK:
1354 if (newvp->v_specmountpoint != NULL) {
1355 delay = metadelay;
1356 break;
1357 }
1358 /* fall through */
1359 default:
1360 delay = filedelay;
1361 }
1362 vn_syncer_add_to_worklist(newvp, delay);
1363 }
1364 bp->b_xflags |= BX_VNDIRTY;
1365 tbp = TAILQ_FIRST(listheadp);
1366 if (tbp == NULL ||
1367 bp->b_lblkno == 0 ||
1368 (bp->b_lblkno > 0 && tbp->b_lblkno < 0) ||
1369 (bp->b_lblkno > 0 && bp->b_lblkno < tbp->b_lblkno)) {
1370 TAILQ_INSERT_HEAD(listheadp, bp, b_vnbufs);
1371 ++reassignbufsortgood;
1372 } else if (bp->b_lblkno < 0) {
1373 TAILQ_INSERT_TAIL(listheadp, bp, b_vnbufs);
1374 ++reassignbufsortgood;
1375 } else if (reassignbufmethod == 1) {
1376 /*
1377 * New sorting algorithm, only handle sequential case,
1378 * otherwise append to end (but before metadata)
1379 */
1380 if ((tbp = gbincore(newvp, bp->b_lblkno - 1)) != NULL &&
1381 (tbp->b_xflags & BX_VNDIRTY)) {
1382 /*
1383 * Found the best place to insert the buffer
1384 */
1385 TAILQ_INSERT_AFTER(listheadp, tbp, bp, b_vnbufs);
1386 ++reassignbufsortgood;
1387 } else {
1388 /*
1389 * Missed, append to end, but before meta-data.
1390 * We know that the head buffer in the list is
1391 * not meta-data due to prior conditionals.
1392 *
1393 * Indirect effects: NFS second stage write
1394 * tends to wind up here, giving maximum
1395 * distance between the unstable write and the
1396 * commit rpc.
1397 */
1398 tbp = TAILQ_LAST(listheadp, buflists);
1399 while (tbp && tbp->b_lblkno < 0)
1400 tbp = TAILQ_PREV(tbp, buflists, b_vnbufs);
1401 TAILQ_INSERT_AFTER(listheadp, tbp, bp, b_vnbufs);
1402 ++reassignbufsortbad;
1403 }
1404 } else {
1405 /*
1406 * Old sorting algorithm, scan queue and insert
1407 */
1408 struct buf *ttbp;
1409 while ((ttbp = TAILQ_NEXT(tbp, b_vnbufs)) &&
1410 (ttbp->b_lblkno < bp->b_lblkno)) {
1411 ++reassignbufloops;
1412 tbp = ttbp;
1413 }
1414 TAILQ_INSERT_AFTER(listheadp, tbp, bp, b_vnbufs);
1415 }
1416 } else {
1417 bp->b_xflags |= BX_VNCLEAN;
1418 TAILQ_INSERT_TAIL(&newvp->v_cleanblkhd, bp, b_vnbufs);
1419 if ((newvp->v_flag & VONWORKLST) &&
1420 TAILQ_EMPTY(&newvp->v_dirtyblkhd)) {
1421 newvp->v_flag &= ~VONWORKLST;
1422 LIST_REMOVE(newvp, v_synclist);
1423 }
1424 }
1425 if (bp->b_vp != newvp) {
1426 bp->b_vp = newvp;
1427 vhold(bp->b_vp);
1428 }
1429 splx(s);
1430}
1431
1432/*
1433 * Create a vnode for a block device.
1434 * Used for mounting the root file system.
1435 */
1436int
1437bdevvp(dev, vpp)
1438 dev_t dev;
1439 struct vnode **vpp;
1440{
1441 register struct vnode *vp;
1442 struct vnode *nvp;
1443 int error;
1444
1445 if (dev == NODEV) {
1446 *vpp = NULLVP;
1447 return (ENXIO);
1448 }
1449 error = getnewvnode(VT_NON, (struct mount *)0, spec_vnodeop_p, &nvp);
1450 if (error) {
1451 *vpp = NULLVP;
1452 return (error);
1453 }
1454 vp = nvp;
1455 vp->v_type = VBLK;
1456 addalias(vp, dev);
1457 *vpp = vp;
1458 return (0);
1459}
1460
1461/*
1462 * Add vnode to the alias list hung off the dev_t.
1463 *
1464 * The reason for this gunk is that multiple vnodes can reference
1465 * the same physical device, so checking vp->v_usecount to see
1466 * how many users there are is inadequate; the v_usecount for
1467 * the vnodes need to be accumulated. vcount() does that.
1468 */
1469void
1470addaliasu(nvp, nvp_rdev)
1471 struct vnode *nvp;
1472 udev_t nvp_rdev;
1473{
1474
1475 if (nvp->v_type != VBLK && nvp->v_type != VCHR)
1476 panic("addaliasu on non-special vnode");
1477 addalias(nvp, udev2dev(nvp_rdev, nvp->v_type == VBLK ? 1 : 0));
1478}
1479
1480void
1481addalias(nvp, dev)
1482 struct vnode *nvp;
1483 dev_t dev;
1484{
1485
1486 if (nvp->v_type != VBLK && nvp->v_type != VCHR)
1487 panic("addalias on non-special vnode");
1488
1489 nvp->v_rdev = dev;
1490 simple_lock(&spechash_slock);
1491 SLIST_INSERT_HEAD(&dev->si_hlist, nvp, v_specnext);
1492 simple_unlock(&spechash_slock);
1493}
1494
1495/*
1496 * Grab a particular vnode from the free list, increment its
1497 * reference count and lock it. The vnode lock bit is set if the
1498 * vnode is being eliminated in vgone. The process is awakened
1499 * when the transition is completed, and an error returned to
1500 * indicate that the vnode is no longer usable (possibly having
1501 * been changed to a new file system type).
1502 */
1503int
1504vget(vp, flags, p)
1505 register struct vnode *vp;
1506 int flags;
1507 struct proc *p;
1508{
1509 int error;
1510
1511 /*
1512 * If the vnode is in the process of being cleaned out for
1513 * another use, we wait for the cleaning to finish and then
1514 * return failure. Cleaning is determined by checking that
1515 * the VXLOCK flag is set.
1516 */
1517 if ((flags & LK_INTERLOCK) == 0) {
1518 simple_lock(&vp->v_interlock);
1519 }
1520 if (vp->v_flag & VXLOCK) {
1521 if (vp->v_vxproc == curproc) {
1522#if 0
1523 /* this can now occur in normal operation */
1524 log(LOG_INFO, "VXLOCK interlock avoided\n");
1525#endif
1526 } else {
1527 vp->v_flag |= VXWANT;
1528 simple_unlock(&vp->v_interlock);
1529 tsleep((caddr_t)vp, PINOD, "vget", 0);
1530 return (ENOENT);
1531 }
1532 }
1533
1534 vp->v_usecount++;
1535
1536 if (VSHOULDBUSY(vp))
1537 vbusy(vp);
1538 if (flags & LK_TYPE_MASK) {
1539 if ((error = vn_lock(vp, flags | LK_INTERLOCK, p)) != 0) {
1540 /*
1541 * must expand vrele here because we do not want
1542 * to call VOP_INACTIVE if the reference count
1543 * drops back to zero since it was never really
1544 * active. We must remove it from the free list
1545 * before sleeping so that multiple processes do
1546 * not try to recycle it.
1547 */
1548 simple_lock(&vp->v_interlock);
1549 vp->v_usecount--;
1550 if (VSHOULDFREE(vp))
1551 vfree(vp);
1552 else
1553 vlruvp(vp);
1554 simple_unlock(&vp->v_interlock);
1555 }
1556 return (error);
1557 }
1558 simple_unlock(&vp->v_interlock);
1559 return (0);
1560}
1561
1562void
1563vref(struct vnode *vp)
1564{
1565 simple_lock(&vp->v_interlock);
1566 vp->v_usecount++;
1567 simple_unlock(&vp->v_interlock);
1568}
1569
1570/*
1571 * Vnode put/release.
1572 * If count drops to zero, call inactive routine and return to freelist.
1573 */
1574void
1575vrele(vp)
1576 struct vnode *vp;
1577{
1578 struct proc *p = curproc; /* XXX */
1579
1580 KASSERT(vp != NULL, ("vrele: null vp"));
1581
1582 simple_lock(&vp->v_interlock);
1583
1584 if (vp->v_usecount > 1) {
1585
1586 vp->v_usecount--;
1587 simple_unlock(&vp->v_interlock);
1588
1589 return;
1590 }
1591
1592 if (vp->v_usecount == 1) {
1593 vp->v_usecount--;
1594 /*
1595 * We must call VOP_INACTIVE with the node locked.
1596 * If we are doing a vpu, the node is already locked,
1597 * but, in the case of vrele, we must explicitly lock
1598 * the vnode before calling VOP_INACTIVE
1599 */
1600
1601 if (vn_lock(vp, LK_EXCLUSIVE | LK_INTERLOCK, p) == 0)
1602 VOP_INACTIVE(vp, p);
1603 if (VSHOULDFREE(vp))
1604 vfree(vp);
1605 else
1606 vlruvp(vp);
1607 } else {
1608#ifdef DIAGNOSTIC
1609 vprint("vrele: negative ref count", vp);
1610 simple_unlock(&vp->v_interlock);
1611#endif
1612 panic("vrele: negative ref cnt");
1613 }
1614}
1615
1616void
1617vput(vp)
1618 struct vnode *vp;
1619{
1620 struct proc *p = curproc; /* XXX */
1621
1622 KASSERT(vp != NULL, ("vput: null vp"));
1623
1624 simple_lock(&vp->v_interlock);
1625
1626 if (vp->v_usecount > 1) {
1627 vp->v_usecount--;
1628 VOP_UNLOCK(vp, LK_INTERLOCK, p);
1629 return;
1630 }
1631
1632 if (vp->v_usecount == 1) {
1633 vp->v_usecount--;
1634 /*
1635 * We must call VOP_INACTIVE with the node locked.
1636 * If we are doing a vpu, the node is already locked,
1637 * so we just need to release the vnode mutex.
1638 */
1639 simple_unlock(&vp->v_interlock);
1640 VOP_INACTIVE(vp, p);
1641 if (VSHOULDFREE(vp))
1642 vfree(vp);
1643 else
1644 vlruvp(vp);
1645 } else {
1646#ifdef DIAGNOSTIC
1647 vprint("vput: negative ref count", vp);
1648#endif
1649 panic("vput: negative ref cnt");
1650 }
1651}
1652
1653/*
1654 * Somebody doesn't want the vnode recycled.
1655 */
1656void
1657vhold(vp)
1658 register struct vnode *vp;
1659{
1660 int s;
1661
1662 s = splbio();
1663 vp->v_holdcnt++;
1664 if (VSHOULDBUSY(vp))
1665 vbusy(vp);
1666 splx(s);
1667}
1668
1669/*
1670 * One less who cares about this vnode.
1671 */
1672void
1673vdrop(vp)
1674 register struct vnode *vp;
1675{
1676 int s;
1677
1678 s = splbio();
1679 if (vp->v_holdcnt <= 0)
1680 panic("vdrop: holdcnt");
1681 vp->v_holdcnt--;
1682 if (VSHOULDFREE(vp))
1683 vfree(vp);
1684 splx(s);
1685}
1686
1687/*
1688 * Remove any vnodes in the vnode table belonging to mount point mp.
1689 *
1690 * If FORCECLOSE is not specified, there should not be any active ones,
1691 * return error if any are found (nb: this is a user error, not a
1692 * system error). If FORCECLOSE is specified, detach any active vnodes
1693 * that are found.
1694 *
1695 * If WRITECLOSE is set, only flush out regular file vnodes open for
1696 * writing.
1697 *
1698 * SKIPSYSTEM causes any vnodes marked VSYSTEM to be skipped.
1699 *
1700 * `rootrefs' specifies the base reference count for the root vnode
1701 * of this filesystem. The root vnode is considered busy if its
1702 * v_usecount exceeds this value. On a successful return, vflush()
1703 * will call vrele() on the root vnode exactly rootrefs times.
1704 * If the SKIPSYSTEM or WRITECLOSE flags are specified, rootrefs must
1705 * be zero.
1706 */
1707#ifdef DIAGNOSTIC
1708static int busyprt = 0; /* print out busy vnodes */
1709SYSCTL_INT(_debug, OID_AUTO, busyprt, CTLFLAG_RW, &busyprt, 0, "");
1710#endif
1711
1712int
1713vflush(mp, rootrefs, flags)
1714 struct mount *mp;
1715 int rootrefs;
1716 int flags;
1717{
1718 struct proc *p = curproc; /* XXX */
1719 struct vnode *vp, *nvp, *rootvp = NULL;
1720 struct vattr vattr;
1721 int busy = 0, error;
1722
1723 if (rootrefs > 0) {
1724 KASSERT((flags & (SKIPSYSTEM | WRITECLOSE)) == 0,
1725 ("vflush: bad args"));
1726 /*
1727 * Get the filesystem root vnode. We can vput() it
1728 * immediately, since with rootrefs > 0, it won't go away.
1729 */
1730 if ((error = VFS_ROOT(mp, &rootvp)) != 0)
1731 return (error);
1732 vput(rootvp);
1733 }
1734 simple_lock(&mntvnode_slock);
1735loop:
1736 for (vp = TAILQ_FIRST(&mp->mnt_nvnodelist); vp; vp = nvp) {
1737 /*
1738 * Make sure this vnode wasn't reclaimed in getnewvnode().
1739 * Start over if it has (it won't be on the list anymore).
1740 */
1741 if (vp->v_mount != mp)
1742 goto loop;
1743 nvp = TAILQ_NEXT(vp, v_nmntvnodes);
1744
1745 simple_lock(&vp->v_interlock);
1746 /*
1747 * Skip over a vnodes marked VSYSTEM.
1748 */
1749 if ((flags & SKIPSYSTEM) && (vp->v_flag & VSYSTEM)) {
1750 simple_unlock(&vp->v_interlock);
1751 continue;
1752 }
1753 /*
1754 * If WRITECLOSE is set, flush out unlinked but still open
1755 * files (even if open only for reading) and regular file
1756 * vnodes open for writing.
1757 */
1758 if ((flags & WRITECLOSE) &&
1759 (vp->v_type == VNON ||
1760 (VOP_GETATTR(vp, &vattr, p->p_ucred, p) == 0 &&
1761 vattr.va_nlink > 0)) &&
1762 (vp->v_writecount == 0 || vp->v_type != VREG)) {
1763 simple_unlock(&vp->v_interlock);
1764 continue;
1765 }
1766
1767 /*
1768 * With v_usecount == 0, all we need to do is clear out the
1769 * vnode data structures and we are done.
1770 */
1771 if (vp->v_usecount == 0) {
1772 simple_unlock(&mntvnode_slock);
1773 vgonel(vp, p);
1774 simple_lock(&mntvnode_slock);
1775 continue;
1776 }
1777
1778 /*
1779 * If FORCECLOSE is set, forcibly close the vnode. For block
1780 * or character devices, revert to an anonymous device. For
1781 * all other files, just kill them.
1782 */
1783 if (flags & FORCECLOSE) {
1784 simple_unlock(&mntvnode_slock);
1785 if (vp->v_type != VBLK && vp->v_type != VCHR) {
1786 vgonel(vp, p);
1787 } else {
1788 vclean(vp, 0, p);
1789 vp->v_op = spec_vnodeop_p;
1790 insmntque(vp, (struct mount *) 0);
1791 }
1792 simple_lock(&mntvnode_slock);
1793 continue;
1794 }
1795#ifdef DIAGNOSTIC
1796 if (busyprt)
1797 vprint("vflush: busy vnode", vp);
1798#endif
1799 simple_unlock(&vp->v_interlock);
1800 busy++;
1801 }
1802 simple_unlock(&mntvnode_slock);
1803 if (rootrefs > 0 && (flags & FORCECLOSE) == 0) {
1804 /*
1805 * If just the root vnode is busy, and if its refcount
1806 * is equal to `rootrefs', then go ahead and kill it.
1807 */
1808 simple_lock(&rootvp->v_interlock);
1809 KASSERT(busy > 0, ("vflush: not busy"));
1810 KASSERT(rootvp->v_usecount >= rootrefs, ("vflush: rootrefs"));
1811 if (busy == 1 && rootvp->v_usecount == rootrefs) {
1812 vgonel(rootvp, p);
1813 busy = 0;
1814 } else
1815 simple_unlock(&rootvp->v_interlock);
1816 }
1817 if (busy)
1818 return (EBUSY);
1819 for (; rootrefs > 0; rootrefs--)
1820 vrele(rootvp);
1821 return (0);
1822}
1823
1824/*
1825 * We do not want to recycle the vnode too quickly.
1826 *
1827 * XXX we can't move vp's around the nvnodelist without really screwing
1828 * up the efficiency of filesystem SYNC and friends. This code is
1829 * disabled until we fix the syncing code's scanning algorithm.
1830 */
1831static void
1832vlruvp(struct vnode *vp)
1833{
1834#if 0
1835 struct mount *mp;
1836
1837 if ((mp = vp->v_mount) != NULL) {
1838 simple_lock(&mntvnode_slock);
1839 TAILQ_REMOVE(&mp->mnt_nvnodelist, vp, v_nmntvnodes);
1840 TAILQ_INSERT_TAIL(&mp->mnt_nvnodelist, vp, v_nmntvnodes);
1841 simple_unlock(&mntvnode_slock);
1842 }
1843#endif
1844}
1845
1846/*
1847 * Disassociate the underlying file system from a vnode.
1848 */
1849static void
1850vclean(vp, flags, p)
1851 struct vnode *vp;
1852 int flags;
1853 struct proc *p;
1854{
1855 int active;
1856
1857 /*
1858 * Check to see if the vnode is in use. If so we have to reference it
1859 * before we clean it out so that its count cannot fall to zero and
1860 * generate a race against ourselves to recycle it.
1861 */
1862 if ((active = vp->v_usecount))
1863 vp->v_usecount++;
1864
1865 /*
1866 * Prevent the vnode from being recycled or brought into use while we
1867 * clean it out.
1868 */
1869 if (vp->v_flag & VXLOCK)
1870 panic("vclean: deadlock");
1871 vp->v_flag |= VXLOCK;
1872 vp->v_vxproc = curproc;
1873 /*
1874 * Even if the count is zero, the VOP_INACTIVE routine may still
1875 * have the object locked while it cleans it out. The VOP_LOCK
1876 * ensures that the VOP_INACTIVE routine is done with its work.
1877 * For active vnodes, it ensures that no other activity can
1878 * occur while the underlying object is being cleaned out.
1879 */
1880 VOP_LOCK(vp, LK_DRAIN | LK_INTERLOCK, p);
1881
1882 /*
1883 * Clean out any buffers associated with the vnode.
1884 */
1885 vinvalbuf(vp, V_SAVE, NOCRED, p, 0, 0);
1886
1887 VOP_DESTROYVOBJECT(vp);
1888
1889 /*
1890 * If purging an active vnode, it must be closed and
1891 * deactivated before being reclaimed. Note that the
1892 * VOP_INACTIVE will unlock the vnode.
1893 */
1894 if (active) {
1895 if (flags & DOCLOSE)
1896 VOP_CLOSE(vp, FNONBLOCK, NOCRED, p);
1897 VOP_INACTIVE(vp, p);
1898 } else {
1899 /*
1900 * Any other processes trying to obtain this lock must first
1901 * wait for VXLOCK to clear, then call the new lock operation.
1902 */
1903 VOP_UNLOCK(vp, 0, p);
1904 }
1905 /*
1906 * Reclaim the vnode.
1907 */
1908 if (VOP_RECLAIM(vp, p))
1909 panic("vclean: cannot reclaim");
1910
1911 if (active) {
1912 /*
1913 * Inline copy of vrele() since VOP_INACTIVE
1914 * has already been called.
1915 */
1916 simple_lock(&vp->v_interlock);
1917 if (--vp->v_usecount <= 0) {
1918#ifdef DIAGNOSTIC
1919 if (vp->v_usecount < 0 || vp->v_writecount != 0) {
1920 vprint("vclean: bad ref count", vp);
1921 panic("vclean: ref cnt");
1922 }
1923#endif
1924 vfree(vp);
1925 }
1926 simple_unlock(&vp->v_interlock);
1927 }
1928
1929 cache_purge(vp);
1930 vp->v_vnlock = NULL;
1931
1932 if (VSHOULDFREE(vp))
1933 vfree(vp);
1934
1935 /*
1936 * Done with purge, notify sleepers of the grim news.
1937 */
1938 vp->v_op = dead_vnodeop_p;
1939 vn_pollgone(vp);
1940 vp->v_tag = VT_NON;
1941 vp->v_flag &= ~VXLOCK;
1942 vp->v_vxproc = NULL;
1943 if (vp->v_flag & VXWANT) {
1944 vp->v_flag &= ~VXWANT;
1945 wakeup((caddr_t) vp);
1946 }
1947}
1948
1949/*
1950 * Eliminate all activity associated with the requested vnode
1951 * and with all vnodes aliased to the requested vnode.
1952 */
1953int
1954vop_revoke(ap)
1955 struct vop_revoke_args /* {
1956 struct vnode *a_vp;
1957 int a_flags;
1958 } */ *ap;
1959{
1960 struct vnode *vp, *vq;
1961 dev_t dev;
1962
1963 KASSERT((ap->a_flags & REVOKEALL) != 0, ("vop_revoke"));
1964
1965 vp = ap->a_vp;
1966 /*
1967 * If a vgone (or vclean) is already in progress,
1968 * wait until it is done and return.
1969 */
1970 if (vp->v_flag & VXLOCK) {
1971 vp->v_flag |= VXWANT;
1972 simple_unlock(&vp->v_interlock);
1973 tsleep((caddr_t)vp, PINOD, "vop_revokeall", 0);
1974 return (0);
1975 }
1976 dev = vp->v_rdev;
1977 for (;;) {
1978 simple_lock(&spechash_slock);
1979 vq = SLIST_FIRST(&dev->si_hlist);
1980 simple_unlock(&spechash_slock);
1981 if (!vq)
1982 break;
1983 vgone(vq);
1984 }
1985 return (0);
1986}
1987
1988/*
1989 * Recycle an unused vnode to the front of the free list.
1990 * Release the passed interlock if the vnode will be recycled.
1991 */
1992int
1993vrecycle(vp, inter_lkp, p)
1994 struct vnode *vp;
1995 struct simplelock *inter_lkp;
1996 struct proc *p;
1997{
1998
1999 simple_lock(&vp->v_interlock);
2000 if (vp->v_usecount == 0) {
2001 if (inter_lkp) {
2002 simple_unlock(inter_lkp);
2003 }
2004 vgonel(vp, p);
2005 return (1);
2006 }
2007 simple_unlock(&vp->v_interlock);
2008 return (0);
2009}
2010
2011/*
2012 * Eliminate all activity associated with a vnode
2013 * in preparation for reuse.
2014 */
2015void
2016vgone(vp)
2017 register struct vnode *vp;
2018{
2019 struct proc *p = curproc; /* XXX */
2020
2021 simple_lock(&vp->v_interlock);
2022 vgonel(vp, p);
2023}
2024
2025/*
2026 * vgone, with the vp interlock held.
2027 */
2028void
2029vgonel(vp, p)
2030 struct vnode *vp;
2031 struct proc *p;
2032{
2033 int s;
2034
2035 /*
2036 * If a vgone (or vclean) is already in progress,
2037 * wait until it is done and return.
2038 */
2039 if (vp->v_flag & VXLOCK) {
2040 vp->v_flag |= VXWANT;
2041 simple_unlock(&vp->v_interlock);
2042 tsleep((caddr_t)vp, PINOD, "vgone", 0);
2043 return;
2044 }
2045
2046 /*
2047 * Clean out the filesystem specific data.
2048 */
2049 vclean(vp, DOCLOSE, p);
2050 simple_lock(&vp->v_interlock);
2051
2052 /*
2053 * Delete from old mount point vnode list, if on one.
2054 */
2055 if (vp->v_mount != NULL)
2056 insmntque(vp, (struct mount *)0);
2057 /*
2058 * If special device, remove it from special device alias list
2059 * if it is on one.
2060 */
2061 if ((vp->v_type == VBLK || vp->v_type == VCHR) && vp->v_rdev != NULL) {
2062 simple_lock(&spechash_slock);
2063 SLIST_REMOVE(&vp->v_hashchain, vp, vnode, v_specnext);
2064 freedev(vp->v_rdev);
2065 simple_unlock(&spechash_slock);
2066 vp->v_rdev = NULL;
2067 }
2068
2069 /*
2070 * If it is on the freelist and not already at the head,
2071 * move it to the head of the list. The test of the
2072 * VDOOMED flag and the reference count of zero is because
2073 * it will be removed from the free list by getnewvnode,
2074 * but will not have its reference count incremented until
2075 * after calling vgone. If the reference count were
2076 * incremented first, vgone would (incorrectly) try to
2077 * close the previous instance of the underlying object.
2078 */
2079 if (vp->v_usecount == 0 && !(vp->v_flag & VDOOMED)) {
2080 s = splbio();
2081 simple_lock(&vnode_free_list_slock);
2082 if (vp->v_flag & VFREE)
2083 TAILQ_REMOVE(&vnode_free_list, vp, v_freelist);
2084 else
2085 freevnodes++;
2086 vp->v_flag |= VFREE;
2087 TAILQ_INSERT_HEAD(&vnode_free_list, vp, v_freelist);
2088 simple_unlock(&vnode_free_list_slock);
2089 splx(s);
2090 }
2091
2092 vp->v_type = VBAD;
2093 simple_unlock(&vp->v_interlock);
2094}
2095
2096/*
2097 * Lookup a vnode by device number.
2098 */
2099int
2100vfinddev(dev, type, vpp)
2101 dev_t dev;
2102 enum vtype type;
2103 struct vnode **vpp;
2104{
2105 struct vnode *vp;
2106
2107 simple_lock(&spechash_slock);
2108 SLIST_FOREACH(vp, &dev->si_hlist, v_specnext) {
2109 if (type == vp->v_type) {
2110 *vpp = vp;
2111 simple_unlock(&spechash_slock);
2112 return (1);
2113 }
2114 }
2115 simple_unlock(&spechash_slock);
2116 return (0);
2117}
2118
2119/*
2120 * Calculate the total number of references to a special device.
2121 */
2122int
2123vcount(vp)
2124 struct vnode *vp;
2125{
2126 struct vnode *vq;
2127 int count;
2128
2129 count = 0;
2130 simple_lock(&spechash_slock);
2131 SLIST_FOREACH(vq, &vp->v_hashchain, v_specnext)
2132 count += vq->v_usecount;
2133 simple_unlock(&spechash_slock);
2134 return (count);
2135}
2136
2137/*
2138 * Same as above, but using the dev_t as argument
2139 */
2140
2141int
2142count_dev(dev)
2143 dev_t dev;
2144{
2145 struct vnode *vp;
2146
2147 vp = SLIST_FIRST(&dev->si_hlist);
2148 if (vp == NULL)
2149 return (0);
2150 return(vcount(vp));
2151}
2152
2153/*
2154 * Print out a description of a vnode.
2155 */
2156static char *typename[] =
2157{"VNON", "VREG", "VDIR", "VBLK", "VCHR", "VLNK", "VSOCK", "VFIFO", "VBAD"};
2158
2159void
2160vprint(label, vp)
2161 char *label;
2162 struct vnode *vp;
2163{
2164 char buf[96];
2165
2166 if (label != NULL)
2167 printf("%s: %p: ", label, (void *)vp);
2168 else
2169 printf("%p: ", (void *)vp);
2170 printf("type %s, usecount %d, writecount %d, refcount %d,",
2171 typename[vp->v_type], vp->v_usecount, vp->v_writecount,
2172 vp->v_holdcnt);
2173 buf[0] = '\0';
2174 if (vp->v_flag & VROOT)
2175 strcat(buf, "|VROOT");
2176 if (vp->v_flag & VTEXT)
2177 strcat(buf, "|VTEXT");
2178 if (vp->v_flag & VSYSTEM)
2179 strcat(buf, "|VSYSTEM");
2180 if (vp->v_flag & VXLOCK)
2181 strcat(buf, "|VXLOCK");
2182 if (vp->v_flag & VXWANT)
2183 strcat(buf, "|VXWANT");
2184 if (vp->v_flag & VBWAIT)
2185 strcat(buf, "|VBWAIT");
2186 if (vp->v_flag & VDOOMED)
2187 strcat(buf, "|VDOOMED");
2188 if (vp->v_flag & VFREE)
2189 strcat(buf, "|VFREE");
2190 if (vp->v_flag & VOBJBUF)
2191 strcat(buf, "|VOBJBUF");
2192 if (buf[0] != '\0')
2193 printf(" flags (%s)", &buf[1]);
2194 if (vp->v_data == NULL) {
2195 printf("\n");
2196 } else {
2197 printf("\n\t");
2198 VOP_PRINT(vp);
2199 }
2200}
2201
2202#ifdef DDB
2203#include <ddb/ddb.h>
2204/*
2205 * List all of the locked vnodes in the system.
2206 * Called when debugging the kernel.
2207 */
2208DB_SHOW_COMMAND(lockedvnodes, lockedvnodes)
2209{
2210 struct proc *p = curproc; /* XXX */
2211 struct mount *mp, *nmp;
2212 struct vnode *vp;
2213
2214 printf("Locked vnodes\n");
2215 simple_lock(&mountlist_slock);
2216 for (mp = TAILQ_FIRST(&mountlist); mp != NULL; mp = nmp) {
2217 if (vfs_busy(mp, LK_NOWAIT, &mountlist_slock, p)) {
2218 nmp = TAILQ_NEXT(mp, mnt_list);
2219 continue;
2220 }
2221 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) {
2222 if (VOP_ISLOCKED(vp, NULL))
2223 vprint((char *)0, vp);
2224 }
2225 simple_lock(&mountlist_slock);
2226 nmp = TAILQ_NEXT(mp, mnt_list);
2227 vfs_unbusy(mp, p);
2228 }
2229 simple_unlock(&mountlist_slock);
2230}
2231#endif
2232
2233/*
2234 * Top level filesystem related information gathering.
2235 */
2236static int sysctl_ovfs_conf __P((SYSCTL_HANDLER_ARGS));
2237
2238static int
2239vfs_sysctl(SYSCTL_HANDLER_ARGS)
2240{
2241 int *name = (int *)arg1 - 1; /* XXX */
2242 u_int namelen = arg2 + 1; /* XXX */
2243 struct vfsconf *vfsp;
2244
2245#if 1 || defined(COMPAT_PRELITE2)
2246 /* Resolve ambiguity between VFS_VFSCONF and VFS_GENERIC. */
2247 if (namelen == 1)
2248 return (sysctl_ovfs_conf(oidp, arg1, arg2, req));
2249#endif
2250
2251#ifdef notyet
2252 /* all sysctl names at this level are at least name and field */
2253 if (namelen < 2)
2254 return (ENOTDIR); /* overloaded */
2255 if (name[0] != VFS_GENERIC) {
2256 for (vfsp = vfsconf; vfsp; vfsp = vfsp->vfc_next)
2257 if (vfsp->vfc_typenum == name[0])
2258 break;
2259 if (vfsp == NULL)
2260 return (EOPNOTSUPP);
2261 return ((*vfsp->vfc_vfsops->vfs_sysctl)(&name[1], namelen - 1,
2262 oldp, oldlenp, newp, newlen, p));
2263 }
2264#endif
2265 switch (name[1]) {
2266 case VFS_MAXTYPENUM:
2267 if (namelen != 2)
2268 return (ENOTDIR);
2269 return (SYSCTL_OUT(req, &maxvfsconf, sizeof(int)));
2270 case VFS_CONF:
2271 if (namelen != 3)
2272 return (ENOTDIR); /* overloaded */
2273 for (vfsp = vfsconf; vfsp; vfsp = vfsp->vfc_next)
2274 if (vfsp->vfc_typenum == name[2])
2275 break;
2276 if (vfsp == NULL)
2277 return (EOPNOTSUPP);
2278 return (SYSCTL_OUT(req, vfsp, sizeof *vfsp));
2279 }
2280 return (EOPNOTSUPP);
2281}
2282
2283SYSCTL_NODE(_vfs, VFS_GENERIC, generic, CTLFLAG_RD, vfs_sysctl,
2284 "Generic filesystem");
2285
2286#if 1 || defined(COMPAT_PRELITE2)
2287
2288static int
2289sysctl_ovfs_conf(SYSCTL_HANDLER_ARGS)
2290{
2291 int error;
2292 struct vfsconf *vfsp;
2293 struct ovfsconf ovfs;
2294
2295 for (vfsp = vfsconf; vfsp; vfsp = vfsp->vfc_next) {
2296 ovfs.vfc_vfsops = vfsp->vfc_vfsops; /* XXX used as flag */
2297 strcpy(ovfs.vfc_name, vfsp->vfc_name);
2298 ovfs.vfc_index = vfsp->vfc_typenum;
2299 ovfs.vfc_refcount = vfsp->vfc_refcount;
2300 ovfs.vfc_flags = vfsp->vfc_flags;
2301 error = SYSCTL_OUT(req, &ovfs, sizeof ovfs);
2302 if (error)
2303 return error;
2304 }
2305 return 0;
2306}
2307
2308#endif /* 1 || COMPAT_PRELITE2 */
2309
2310#if 0
2311#define KINFO_VNODESLOP 10
2312/*
2313 * Dump vnode list (via sysctl).
2314 * Copyout address of vnode followed by vnode.
2315 */
2316/* ARGSUSED */
2317static int
2318sysctl_vnode(SYSCTL_HANDLER_ARGS)
2319{
2320 struct proc *p = curproc; /* XXX */
2321 struct mount *mp, *nmp;
2322 struct vnode *nvp, *vp;
2323 int error;
2324
2325#define VPTRSZ sizeof (struct vnode *)
2326#define VNODESZ sizeof (struct vnode)
2327
2328 req->lock = 0;
2329 if (!req->oldptr) /* Make an estimate */
2330 return (SYSCTL_OUT(req, 0,
2331 (numvnodes + KINFO_VNODESLOP) * (VPTRSZ + VNODESZ)));
2332
2333 simple_lock(&mountlist_slock);
2334 for (mp = TAILQ_FIRST(&mountlist); mp != NULL; mp = nmp) {
2335 if (vfs_busy(mp, LK_NOWAIT, &mountlist_slock, p)) {
2336 nmp = TAILQ_NEXT(mp, mnt_list);
2337 continue;
2338 }
2339again:
2340 simple_lock(&mntvnode_slock);
2341 for (vp = TAILQ_FIRST(&mp->mnt_nvnodelist);
2342 vp != NULL;
2343 vp = nvp) {
2344 /*
2345 * Check that the vp is still associated with
2346 * this filesystem. RACE: could have been
2347 * recycled onto the same filesystem.
2348 */
2349 if (vp->v_mount != mp) {
2350 simple_unlock(&mntvnode_slock);
2351 goto again;
2352 }
2353 nvp = TAILQ_NEXT(vp, v_nmntvnodes);
2354 simple_unlock(&mntvnode_slock);
2355 if ((error = SYSCTL_OUT(req, &vp, VPTRSZ)) ||
2356 (error = SYSCTL_OUT(req, vp, VNODESZ)))
2357 return (error);
2358 simple_lock(&mntvnode_slock);
2359 }
2360 simple_unlock(&mntvnode_slock);
2361 simple_lock(&mountlist_slock);
2362 nmp = TAILQ_NEXT(mp, mnt_list);
2363 vfs_unbusy(mp, p);
2364 }
2365 simple_unlock(&mountlist_slock);
2366
2367 return (0);
2368}
2369#endif
2370
2371/*
2372 * XXX
2373 * Exporting the vnode list on large systems causes them to crash.
2374 * Exporting the vnode list on medium systems causes sysctl to coredump.
2375 */
2376#if 0
2377SYSCTL_PROC(_kern, KERN_VNODE, vnode, CTLTYPE_OPAQUE|CTLFLAG_RD,
2378 0, 0, sysctl_vnode, "S,vnode", "");
2379#endif
2380
2381/*
2382 * Check to see if a filesystem is mounted on a block device.
2383 */
2384int
2385vfs_mountedon(vp)
2386 struct vnode *vp;
2387{
2388
2389 if (vp->v_specmountpoint != NULL)
2390 return (EBUSY);
2391 return (0);
2392}
2393
2394/*
2395 * Unmount all filesystems. The list is traversed in reverse order
2396 * of mounting to avoid dependencies.
2397 */
2398void
2399vfs_unmountall()
2400{
2401 struct mount *mp;
2402 struct proc *p;
2403 int error;
2404
2405 if (curproc != NULL)
2406 p = curproc;
2407 else
2408 p = initproc; /* XXX XXX should this be proc0? */
2409 /*
2410 * Since this only runs when rebooting, it is not interlocked.
2411 */
2412 while(!TAILQ_EMPTY(&mountlist)) {
2413 mp = TAILQ_LAST(&mountlist, mntlist);
2414 error = dounmount(mp, MNT_FORCE, p);
2415 if (error) {
2416 TAILQ_REMOVE(&mountlist, mp, mnt_list);
2417 printf("unmount of %s failed (",
2418 mp->mnt_stat.f_mntonname);
2419 if (error == EBUSY)
2420 printf("BUSY)\n");
2421 else
2422 printf("%d)\n", error);
2423 } else {
2424 /* The unmount has removed mp from the mountlist */
2425 }
2426 }
2427}
2428
2429/*
2430 * Build hash lists of net addresses and hang them off the mount point.
2431 * Called by ufs_mount() to set up the lists of export addresses.
2432 */
2433static int
2434vfs_hang_addrlist(mp, nep, argp)
2435 struct mount *mp;
2436 struct netexport *nep;
2437 struct export_args *argp;
2438{
2439 register struct netcred *np;
2440 register struct radix_node_head *rnh;
2441 register int i;
2442 struct radix_node *rn;
2443 struct sockaddr *saddr, *smask = 0;
2444 struct domain *dom;
2445 int error;
2446
2447 if (argp->ex_addrlen == 0) {
2448 if (mp->mnt_flag & MNT_DEFEXPORTED)
2449 return (EPERM);
2450 np = &nep->ne_defexported;
2451 np->netc_exflags = argp->ex_flags;
2452 np->netc_anon = argp->ex_anon;
2453 np->netc_anon.cr_ref = 1;
2454 mp->mnt_flag |= MNT_DEFEXPORTED;
2455 return (0);
2456 }
2457
2458 if (argp->ex_addrlen > MLEN)
2459 return (EINVAL);
2460
2461 i = sizeof(struct netcred) + argp->ex_addrlen + argp->ex_masklen;
2462 np = (struct netcred *) malloc(i, M_NETADDR, M_WAITOK);
2463 bzero((caddr_t) np, i);
2464 saddr = (struct sockaddr *) (np + 1);
2465 if ((error = copyin(argp->ex_addr, (caddr_t) saddr, argp->ex_addrlen)))
2466 goto out;
2467 if (saddr->sa_len > argp->ex_addrlen)
2468 saddr->sa_len = argp->ex_addrlen;
2469 if (argp->ex_masklen) {
2470 smask = (struct sockaddr *) ((caddr_t) saddr + argp->ex_addrlen);
2471 error = copyin(argp->ex_mask, (caddr_t) smask, argp->ex_masklen);
2472 if (error)
2473 goto out;
2474 if (smask->sa_len > argp->ex_masklen)
2475 smask->sa_len = argp->ex_masklen;
2476 }
2477 i = saddr->sa_family;
2478 if ((rnh = nep->ne_rtable[i]) == 0) {
2479 /*
2480 * Seems silly to initialize every AF when most are not used,
2481 * do so on demand here
2482 */
2483 for (dom = domains; dom; dom = dom->dom_next)
2484 if (dom->dom_family == i && dom->dom_rtattach) {
2485 dom->dom_rtattach((void **) &nep->ne_rtable[i],
2486 dom->dom_rtoffset);
2487 break;
2488 }
2489 if ((rnh = nep->ne_rtable[i]) == 0) {
2490 error = ENOBUFS;
2491 goto out;
2492 }
2493 }
2494 rn = (*rnh->rnh_addaddr) ((caddr_t) saddr, (caddr_t) smask, rnh,
2495 np->netc_rnodes);
2496 if (rn == 0 || np != (struct netcred *) rn) { /* already exists */
2497 error = EPERM;
2498 goto out;
2499 }
2500 np->netc_exflags = argp->ex_flags;
2501 np->netc_anon = argp->ex_anon;
2502 np->netc_anon.cr_ref = 1;
2503 return (0);
2504out:
2505 free(np, M_NETADDR);
2506 return (error);
2507}
2508
2509/* ARGSUSED */
2510static int
2511vfs_free_netcred(rn, w)
2512 struct radix_node *rn;
2513 void *w;
2514{
2515 register struct radix_node_head *rnh = (struct radix_node_head *) w;
2516
2517 (*rnh->rnh_deladdr) (rn->rn_key, rn->rn_mask, rnh);
2518 free((caddr_t) rn, M_NETADDR);
2519 return (0);
2520}
2521
2522/*
2523 * Free the net address hash lists that are hanging off the mount points.
2524 */
2525static void
2526vfs_free_addrlist(nep)
2527 struct netexport *nep;
2528{
2529 register int i;
2530 register struct radix_node_head *rnh;
2531
2532 for (i = 0; i <= AF_MAX; i++)
2533 if ((rnh = nep->ne_rtable[i])) {
2534 (*rnh->rnh_walktree) (rnh, vfs_free_netcred,
2535 (caddr_t) rnh);
2536 free((caddr_t) rnh, M_RTABLE);
2537 nep->ne_rtable[i] = 0;
2538 }
2539}
2540
2541int
2542vfs_export(mp, nep, argp)
2543 struct mount *mp;
2544 struct netexport *nep;
2545 struct export_args *argp;
2546{
2547 int error;
2548
2549 if (argp->ex_flags & MNT_DELEXPORT) {
2550 if (mp->mnt_flag & MNT_EXPUBLIC) {
2551 vfs_setpublicfs(NULL, NULL, NULL);
2552 mp->mnt_flag &= ~MNT_EXPUBLIC;
2553 }
2554 vfs_free_addrlist(nep);
2555 mp->mnt_flag &= ~(MNT_EXPORTED | MNT_DEFEXPORTED);
2556 }
2557 if (argp->ex_flags & MNT_EXPORTED) {
2558 if (argp->ex_flags & MNT_EXPUBLIC) {
2559 if ((error = vfs_setpublicfs(mp, nep, argp)) != 0)
2560 return (error);
2561 mp->mnt_flag |= MNT_EXPUBLIC;
2562 }
2563 if ((error = vfs_hang_addrlist(mp, nep, argp)))
2564 return (error);
2565 mp->mnt_flag |= MNT_EXPORTED;
2566 }
2567 return (0);
2568}
2569
2570
2571/*
2572 * Set the publicly exported filesystem (WebNFS). Currently, only
2573 * one public filesystem is possible in the spec (RFC 2054 and 2055)
2574 */
2575int
2576vfs_setpublicfs(mp, nep, argp)
2577 struct mount *mp;
2578 struct netexport *nep;
2579 struct export_args *argp;
2580{
2581 int error;
2582 struct vnode *rvp;
2583 char *cp;
2584
2585 /*
2586 * mp == NULL -> invalidate the current info, the FS is
2587 * no longer exported. May be called from either vfs_export
2588 * or unmount, so check if it hasn't already been done.
2589 */
2590 if (mp == NULL) {
2591 if (nfs_pub.np_valid) {
2592 nfs_pub.np_valid = 0;
2593 if (nfs_pub.np_index != NULL) {
2594 FREE(nfs_pub.np_index, M_TEMP);
2595 nfs_pub.np_index = NULL;
2596 }
2597 }
2598 return (0);
2599 }
2600
2601 /*
2602 * Only one allowed at a time.
2603 */
2604 if (nfs_pub.np_valid != 0 && mp != nfs_pub.np_mount)
2605 return (EBUSY);
2606
2607 /*
2608 * Get real filehandle for root of exported FS.
2609 */
2610 bzero((caddr_t)&nfs_pub.np_handle, sizeof(nfs_pub.np_handle));
2611 nfs_pub.np_handle.fh_fsid = mp->mnt_stat.f_fsid;
2612
2613 if ((error = VFS_ROOT(mp, &rvp)))
2614 return (error);
2615
2616 if ((error = VFS_VPTOFH(rvp, &nfs_pub.np_handle.fh_fid)))
2617 return (error);
2618
2619 vput(rvp);
2620
2621 /*
2622 * If an indexfile was specified, pull it in.
2623 */
2624 if (argp->ex_indexfile != NULL) {
2625 MALLOC(nfs_pub.np_index, char *, MAXNAMLEN + 1, M_TEMP,
2626 M_WAITOK);
2627 error = copyinstr(argp->ex_indexfile, nfs_pub.np_index,
2628 MAXNAMLEN, (size_t *)0);
2629 if (!error) {
2630 /*
2631 * Check for illegal filenames.
2632 */
2633 for (cp = nfs_pub.np_index; *cp; cp++) {
2634 if (*cp == '/') {
2635 error = EINVAL;
2636 break;
2637 }
2638 }
2639 }
2640 if (error) {
2641 FREE(nfs_pub.np_index, M_TEMP);
2642 return (error);
2643 }
2644 }
2645
2646 nfs_pub.np_mount = mp;
2647 nfs_pub.np_valid = 1;
2648 return (0);
2649}
2650
2651struct netcred *
2652vfs_export_lookup(mp, nep, nam)
2653 register struct mount *mp;
2654 struct netexport *nep;
2655 struct sockaddr *nam;
2656{
2657 register struct netcred *np;
2658 register struct radix_node_head *rnh;
2659 struct sockaddr *saddr;
2660
2661 np = NULL;
2662 if (mp->mnt_flag & MNT_EXPORTED) {
2663 /*
2664 * Lookup in the export list first.
2665 */
2666 if (nam != NULL) {
2667 saddr = nam;
2668 rnh = nep->ne_rtable[saddr->sa_family];
2669 if (rnh != NULL) {
2670 np = (struct netcred *)
2671 (*rnh->rnh_matchaddr)((caddr_t)saddr,
2672 rnh);
2673 if (np && np->netc_rnodes->rn_flags & RNF_ROOT)
2674 np = NULL;
2675 }
2676 }
2677 /*
2678 * If no address match, use the default if it exists.
2679 */
2680 if (np == NULL && mp->mnt_flag & MNT_DEFEXPORTED)
2681 np = &nep->ne_defexported;
2682 }
2683 return (np);
2684}
2685
2686/*
2687 * perform msync on all vnodes under a mount point
2688 * the mount point must be locked.
2689 */
2690void
2691vfs_msync(struct mount *mp, int flags)
2692{
2693 struct vnode *vp, *nvp;
2694 struct vm_object *obj;
2695 int tries;
2696
2697 tries = 5;
2698 simple_lock(&mntvnode_slock);
2699loop:
2700 for (vp = TAILQ_FIRST(&mp->mnt_nvnodelist); vp != NULL; vp = nvp) {
2701 if (vp->v_mount != mp) {
2702 if (--tries > 0)
2703 goto loop;
2704 break;
2705 }
2706 nvp = TAILQ_NEXT(vp, v_nmntvnodes);
2707
2708 if (vp->v_flag & VXLOCK) /* XXX: what if MNT_WAIT? */
2709 continue;
2710
2711 /*
2712 * There could be hundreds of thousands of vnodes, we cannot
2713 * afford to do anything heavy-weight until we have a fairly
2714 * good indication that there is something to do.
2715 */
2716 if ((vp->v_flag & VOBJDIRTY) &&
2717 (flags == MNT_WAIT || VOP_ISLOCKED(vp, NULL) == 0)) {
2718 simple_unlock(&mntvnode_slock);
2719 if (!vget(vp,
2720 LK_EXCLUSIVE | LK_RETRY | LK_NOOBJ, curproc)) {
2721 if (VOP_GETVOBJECT(vp, &obj) == 0) {
2722 vm_object_page_clean(obj, 0, 0, flags == MNT_WAIT ? OBJPC_SYNC : OBJPC_NOSYNC);
2723 }
2724 vput(vp);
2725 }
2726 simple_lock(&mntvnode_slock);
2727 if (TAILQ_NEXT(vp, v_nmntvnodes) != nvp) {
2728 if (--tries > 0)
2729 goto loop;
2730 break;
2731 }
2732 }
2733 }
2734 simple_unlock(&mntvnode_slock);
2735}
2736
2737/*
2738 * Create the VM object needed for VMIO and mmap support. This
2739 * is done for all VREG files in the system. Some filesystems might
2740 * afford the additional metadata buffering capability of the
2741 * VMIO code by making the device node be VMIO mode also.
2742 *
2743 * vp must be locked when vfs_object_create is called.
2744 */
2745int
2746vfs_object_create(vp, p, cred)
2747 struct vnode *vp;
2748 struct proc *p;
2749 struct ucred *cred;
2750{
2751 return (VOP_CREATEVOBJECT(vp, cred, p));
2752}
2753
2754void
2755vfree(vp)
2756 struct vnode *vp;
2757{
2758 int s;
2759
2760 s = splbio();
2761 simple_lock(&vnode_free_list_slock);
2762 KASSERT((vp->v_flag & VFREE) == 0, ("vnode already free"));
2763 if (vp->v_flag & VAGE) {
2764 TAILQ_INSERT_HEAD(&vnode_free_list, vp, v_freelist);
2765 } else {
2766 TAILQ_INSERT_TAIL(&vnode_free_list, vp, v_freelist);
2767 }
2768 freevnodes++;
2769 simple_unlock(&vnode_free_list_slock);
2770 vp->v_flag &= ~VAGE;
2771 vp->v_flag |= VFREE;
2772 splx(s);
2773}
2774
2775void
2776vbusy(vp)
2777 struct vnode *vp;
2778{
2779 int s;
2780
2781 s = splbio();
2782 simple_lock(&vnode_free_list_slock);
2783 KASSERT((vp->v_flag & VFREE) != 0, ("vnode not free"));
2784 TAILQ_REMOVE(&vnode_free_list, vp, v_freelist);
2785 freevnodes--;
2786 simple_unlock(&vnode_free_list_slock);
2787 vp->v_flag &= ~(VFREE|VAGE);
2788 splx(s);
2789}
2790
2791/*
2792 * Record a process's interest in events which might happen to
2793 * a vnode. Because poll uses the historic select-style interface
2794 * internally, this routine serves as both the ``check for any
2795 * pending events'' and the ``record my interest in future events''
2796 * functions. (These are done together, while the lock is held,
2797 * to avoid race conditions.)
2798 */
2799int
2800vn_pollrecord(vp, p, events)
2801 struct vnode *vp;
2802 struct proc *p;
2803 short events;
2804{
2805 simple_lock(&vp->v_pollinfo.vpi_lock);
2806 if (vp->v_pollinfo.vpi_revents & events) {
2807 /*
2808 * This leaves events we are not interested
2809 * in available for the other process which
2810 * which presumably had requested them
2811 * (otherwise they would never have been
2812 * recorded).
2813 */
2814 events &= vp->v_pollinfo.vpi_revents;
2815 vp->v_pollinfo.vpi_revents &= ~events;
2816
2817 simple_unlock(&vp->v_pollinfo.vpi_lock);
2818 return events;
2819 }
2820 vp->v_pollinfo.vpi_events |= events;
2821 selrecord(p, &vp->v_pollinfo.vpi_selinfo);
2822 simple_unlock(&vp->v_pollinfo.vpi_lock);
2823 return 0;
2824}
2825
2826/*
2827 * Note the occurrence of an event. If the VN_POLLEVENT macro is used,
2828 * it is possible for us to miss an event due to race conditions, but
2829 * that condition is expected to be rare, so for the moment it is the
2830 * preferred interface.
2831 */
2832void
2833vn_pollevent(vp, events)
2834 struct vnode *vp;
2835 short events;
2836{
2837 simple_lock(&vp->v_pollinfo.vpi_lock);
2838 if (vp->v_pollinfo.vpi_events & events) {
2839 /*
2840 * We clear vpi_events so that we don't
2841 * call selwakeup() twice if two events are
2842 * posted before the polling process(es) is
2843 * awakened. This also ensures that we take at
2844 * most one selwakeup() if the polling process
2845 * is no longer interested. However, it does
2846 * mean that only one event can be noticed at
2847 * a time. (Perhaps we should only clear those
2848 * event bits which we note?) XXX
2849 */
2850 vp->v_pollinfo.vpi_events = 0; /* &= ~events ??? */
2851 vp->v_pollinfo.vpi_revents |= events;
2852 selwakeup(&vp->v_pollinfo.vpi_selinfo);
2853 }
2854 simple_unlock(&vp->v_pollinfo.vpi_lock);
2855}
2856
2857/*
2858 * Wake up anyone polling on vp because it is being revoked.
2859 * This depends on dead_poll() returning POLLHUP for correct
2860 * behavior.
2861 */
2862void
2863vn_pollgone(vp)
2864 struct vnode *vp;
2865{
2866 simple_lock(&vp->v_pollinfo.vpi_lock);
2867 if (vp->v_pollinfo.vpi_events) {
2868 vp->v_pollinfo.vpi_events = 0;
2869 selwakeup(&vp->v_pollinfo.vpi_selinfo);
2870 }
2871 simple_unlock(&vp->v_pollinfo.vpi_lock);
2872}
2873
2874
2875
2876/*
2877 * Routine to create and manage a filesystem syncer vnode.
2878 */
2879#define sync_close ((int (*) __P((struct vop_close_args *)))nullop)
2880static int sync_fsync __P((struct vop_fsync_args *));
2881static int sync_inactive __P((struct vop_inactive_args *));
2882static int sync_reclaim __P((struct vop_reclaim_args *));
2883#define sync_lock ((int (*) __P((struct vop_lock_args *)))vop_nolock)
2884#define sync_unlock ((int (*) __P((struct vop_unlock_args *)))vop_nounlock)
2885static int sync_print __P((struct vop_print_args *));
2886#define sync_islocked ((int(*) __P((struct vop_islocked_args *)))vop_noislocked)
2887
2888static vop_t **sync_vnodeop_p;
2889static struct vnodeopv_entry_desc sync_vnodeop_entries[] = {
2890 { &vop_default_desc, (vop_t *) vop_eopnotsupp },
2891 { &vop_close_desc, (vop_t *) sync_close }, /* close */
2892 { &vop_fsync_desc, (vop_t *) sync_fsync }, /* fsync */
2893 { &vop_inactive_desc, (vop_t *) sync_inactive }, /* inactive */
2894 { &vop_reclaim_desc, (vop_t *) sync_reclaim }, /* reclaim */
2895 { &vop_lock_desc, (vop_t *) sync_lock }, /* lock */
2896 { &vop_unlock_desc, (vop_t *) sync_unlock }, /* unlock */
2897 { &vop_print_desc, (vop_t *) sync_print }, /* print */
2898 { &vop_islocked_desc, (vop_t *) sync_islocked }, /* islocked */
2899 { NULL, NULL }
2900};
2901static struct vnodeopv_desc sync_vnodeop_opv_desc =
2902 { &sync_vnodeop_p, sync_vnodeop_entries };
2903
2904VNODEOP_SET(sync_vnodeop_opv_desc);
2905
2906/*
2907 * Create a new filesystem syncer vnode for the specified mount point.
2908 */
2909int
2910vfs_allocate_syncvnode(mp)
2911 struct mount *mp;
2912{
2913 struct vnode *vp;
2914 static long start, incr, next;
2915 int error;
2916
2917 /* Allocate a new vnode */
2918 if ((error = getnewvnode(VT_VFS, mp, sync_vnodeop_p, &vp)) != 0) {
2919 mp->mnt_syncer = NULL;
2920 return (error);
2921 }
2922 vp->v_type = VNON;
2923 /*
2924 * Place the vnode onto the syncer worklist. We attempt to
2925 * scatter them about on the list so that they will go off
2926 * at evenly distributed times even if all the filesystems
2927 * are mounted at once.
2928 */
2929 next += incr;
2930 if (next == 0 || next > syncer_maxdelay) {
2931 start /= 2;
2932 incr /= 2;
2933 if (start == 0) {
2934 start = syncer_maxdelay / 2;
2935 incr = syncer_maxdelay;
2936 }
2937 next = start;
2938 }
2939 vn_syncer_add_to_worklist(vp, syncdelay > 0 ? next % syncdelay : 0);
2940 mp->mnt_syncer = vp;
2941 return (0);
2942}
2943
2944/*
2945 * Do a lazy sync of the filesystem.
2946 */
2947static int
2948sync_fsync(ap)
2949 struct vop_fsync_args /* {
2950 struct vnode *a_vp;
2951 struct ucred *a_cred;
2952 int a_waitfor;
2953 struct proc *a_p;
2954 } */ *ap;
2955{
2956 struct vnode *syncvp = ap->a_vp;
2957 struct mount *mp = syncvp->v_mount;
2958 struct proc *p = ap->a_p;
2959 int asyncflag;
2960
2961 /*
2962 * We only need to do something if this is a lazy evaluation.
2963 */
2964 if (ap->a_waitfor != MNT_LAZY)
2965 return (0);
2966
2967 /*
2968 * Move ourselves to the back of the sync list.
2969 */
2970 vn_syncer_add_to_worklist(syncvp, syncdelay);
2971
2972 /*
2973 * Walk the list of vnodes pushing all that are dirty and
2974 * not already on the sync list.
2975 */
2976 simple_lock(&mountlist_slock);
2977 if (vfs_busy(mp, LK_EXCLUSIVE | LK_NOWAIT, &mountlist_slock, p) != 0) {
2978 simple_unlock(&mountlist_slock);
2979 return (0);
2980 }
2981 asyncflag = mp->mnt_flag & MNT_ASYNC;
2982 mp->mnt_flag &= ~MNT_ASYNC;
2983 vfs_msync(mp, MNT_NOWAIT);
2984 VFS_SYNC(mp, MNT_LAZY, ap->a_cred, p);
2985 if (asyncflag)
2986 mp->mnt_flag |= MNT_ASYNC;
2987 vfs_unbusy(mp, p);
2988 return (0);
2989}
2990
2991/*
2992 * The syncer vnode is no referenced.
2993 */
2994static int
2995sync_inactive(ap)
2996 struct vop_inactive_args /* {
2997 struct vnode *a_vp;
2998 struct proc *a_p;
2999 } */ *ap;
3000{
3001
3002 vgone(ap->a_vp);
3003 return (0);
3004}
3005
3006/*
3007 * The syncer vnode is no longer needed and is being decommissioned.
3008 *
3009 * Modifications to the worklist must be protected at splbio().
3010 */
3011static int
3012sync_reclaim(ap)
3013 struct vop_reclaim_args /* {
3014 struct vnode *a_vp;
3015 } */ *ap;
3016{
3017 struct vnode *vp = ap->a_vp;
3018 int s;
3019
3020 s = splbio();
3021 vp->v_mount->mnt_syncer = NULL;
3022 if (vp->v_flag & VONWORKLST) {
3023 LIST_REMOVE(vp, v_synclist);
3024 vp->v_flag &= ~VONWORKLST;
3025 }
3026 splx(s);
3027
3028 return (0);
3029}
3030
3031/*
3032 * Print out a syncer vnode.
3033 */
3034static int
3035sync_print(ap)
3036 struct vop_print_args /* {
3037 struct vnode *a_vp;
3038 } */ *ap;
3039{
3040 struct vnode *vp = ap->a_vp;
3041
3042 printf("syncer vnode");
3043 if (vp->v_vnlock != NULL)
3044 lockmgr_printinfo(vp->v_vnlock);
3045 printf("\n");
3046 return (0);
3047}
3048
3049/*
3050 * extract the dev_t from a VBLK or VCHR
3051 */
3052dev_t
3053vn_todev(vp)
3054 struct vnode *vp;
3055{
3056 if (vp->v_type != VBLK && vp->v_type != VCHR)
3057 return (NODEV);
3058 return (vp->v_rdev);
3059}
3060
3061/*
3062 * Check if vnode represents a disk device
3063 */
3064int
3065vn_isdisk(vp, errp)
3066 struct vnode *vp;
3067 int *errp;
3068{
3069 if (vp->v_type != VBLK && vp->v_type != VCHR) {
3070 if (errp != NULL)
3071 *errp = ENOTBLK;
3072 return (0);
3073 }
3074 if (vp->v_rdev == NULL) {
3075 if (errp != NULL)
3076 *errp = ENXIO;
3077 return (0);
3078 }
3079 if (!devsw(vp->v_rdev)) {
3080 if (errp != NULL)
3081 *errp = ENXIO;
3082 return (0);
3083 }
3084 if (!(devsw(vp->v_rdev)->d_flags & D_DISK)) {
3085 if (errp != NULL)
3086 *errp = ENOTBLK;
3087 return (0);
3088 }
3089 if (errp != NULL)
3090 *errp = 0;
3091 return (1);
3092}
3093
3094void
3095NDFREE(ndp, flags)
3096 struct nameidata *ndp;
3097 const uint flags;
3098{
3099 if (!(flags & NDF_NO_FREE_PNBUF) &&
3100 (ndp->ni_cnd.cn_flags & HASBUF)) {
3101 zfree(namei_zone, ndp->ni_cnd.cn_pnbuf);
3102 ndp->ni_cnd.cn_flags &= ~HASBUF;
3103 }
3104 if (!(flags & NDF_NO_DVP_UNLOCK) &&
3105 (ndp->ni_cnd.cn_flags & LOCKPARENT) &&
3106 ndp->ni_dvp != ndp->ni_vp)
3107 VOP_UNLOCK(ndp->ni_dvp, 0, ndp->ni_cnd.cn_proc);
3108 if (!(flags & NDF_NO_DVP_RELE) &&
3109 (ndp->ni_cnd.cn_flags & (LOCKPARENT|WANTPARENT))) {
3110 vrele(ndp->ni_dvp);
3111 ndp->ni_dvp = NULL;
3112 }
3113 if (!(flags & NDF_NO_VP_UNLOCK) &&
3114 (ndp->ni_cnd.cn_flags & LOCKLEAF) && ndp->ni_vp)
3115 VOP_UNLOCK(ndp->ni_vp, 0, ndp->ni_cnd.cn_proc);
3116 if (!(flags & NDF_NO_VP_RELE) &&
3117 ndp->ni_vp) {
3118 vrele(ndp->ni_vp);
3119 ndp->ni_vp = NULL;
3120 }
3121 if (!(flags & NDF_NO_STARTDIR_RELE) &&
3122 (ndp->ni_cnd.cn_flags & SAVESTART)) {
3123 vrele(ndp->ni_startdir);
3124 ndp->ni_startdir = NULL;
3125 }
3126}