1 /*
2 * Copyright (c) 1989, 1993
3 * The Regents of the University of California. All rights reserved.
4 *
5 * This code is derived from software contributed
6 * to Berkeley by John Heidemann of the UCLA Ficus project.
7 *
8 * Source: * @(#)i405_init.c 2.10 92/04/27 UCLA Ficus project
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 *
39 * $FreeBSD: releng/5.1/sys/kern/vfs_default.c 114774 2003-05-06 02:45:28Z alc $
40 */
41
42 #include <sys/param.h>
43 #include <sys/systm.h>
44 #include <sys/bio.h>
45 #include <sys/buf.h>
46 #include <sys/conf.h>
47 #include <sys/kernel.h>
48 #include <sys/limits.h>
49 #include <sys/lock.h>
50 #include <sys/malloc.h>
51 #include <sys/mount.h>
52 #include <sys/mutex.h>
53 #include <sys/unistd.h>
54 #include <sys/vnode.h>
55 #include <sys/poll.h>
56
57 #include <vm/vm.h>
58 #include <vm/vm_object.h>
59 #include <vm/vm_extern.h>
60 #include <vm/pmap.h>
61 #include <vm/vm_map.h>
62 #include <vm/vm_page.h>
63 #include <vm/vm_pager.h>
64 #include <vm/vnode_pager.h>
65
66 static int vop_nolookup(struct vop_lookup_args *);
67 static int vop_nostrategy(struct vop_strategy_args *);
68 static int vop_nospecstrategy(struct vop_specstrategy_args *);
69
70 /*
71 * This vnode table stores what we want to do if the filesystem doesn't
72 * implement a particular VOP.
73 *
74 * If there is no specific entry here, we will return EOPNOTSUPP.
75 *
76 */
77
78 vop_t **default_vnodeop_p;
79 static struct vnodeopv_entry_desc default_vnodeop_entries[] = {
80 { &vop_default_desc, (vop_t *) vop_eopnotsupp },
81 { &vop_advlock_desc, (vop_t *) vop_einval },
82 { &vop_bmap_desc, (vop_t *) vop_stdbmap },
83 { &vop_close_desc, (vop_t *) vop_null },
84 { &vop_createvobject_desc, (vop_t *) vop_stdcreatevobject },
85 { &vop_destroyvobject_desc, (vop_t *) vop_stddestroyvobject },
86 { &vop_fsync_desc, (vop_t *) vop_null },
87 { &vop_getpages_desc, (vop_t *) vop_stdgetpages },
88 { &vop_getvobject_desc, (vop_t *) vop_stdgetvobject },
89 { &vop_inactive_desc, (vop_t *) vop_stdinactive },
90 { &vop_ioctl_desc, (vop_t *) vop_enotty },
91 { &vop_islocked_desc, (vop_t *) vop_stdislocked },
92 { &vop_lease_desc, (vop_t *) vop_null },
93 { &vop_lock_desc, (vop_t *) vop_stdlock },
94 { &vop_lookup_desc, (vop_t *) vop_nolookup },
95 { &vop_open_desc, (vop_t *) vop_null },
96 { &vop_pathconf_desc, (vop_t *) vop_einval },
97 { &vop_poll_desc, (vop_t *) vop_nopoll },
98 { &vop_putpages_desc, (vop_t *) vop_stdputpages },
99 { &vop_readlink_desc, (vop_t *) vop_einval },
100 { &vop_revoke_desc, (vop_t *) vop_revoke },
101 { &vop_specstrategy_desc, (vop_t *) vop_nospecstrategy },
102 { &vop_strategy_desc, (vop_t *) vop_nostrategy },
103 { &vop_unlock_desc, (vop_t *) vop_stdunlock },
104 { NULL, NULL }
105 };
106
107 static struct vnodeopv_desc default_vnodeop_opv_desc =
108 { &default_vnodeop_p, default_vnodeop_entries };
109
110 VNODEOP_SET(default_vnodeop_opv_desc);
111
112 /*
113 * Series of placeholder functions for various error returns for
114 * VOPs.
115 */
116
117 int
118 vop_eopnotsupp(struct vop_generic_args *ap)
119 {
120 /*
121 printf("vop_notsupp[%s]\n", ap->a_desc->vdesc_name);
122 */
123
124 return (EOPNOTSUPP);
125 }
126
127 int
128 vop_ebadf(struct vop_generic_args *ap)
129 {
130
131 return (EBADF);
132 }
133
134 int
135 vop_enotty(struct vop_generic_args *ap)
136 {
137
138 return (ENOTTY);
139 }
140
141 int
142 vop_einval(struct vop_generic_args *ap)
143 {
144
145 return (EINVAL);
146 }
147
148 int
149 vop_null(struct vop_generic_args *ap)
150 {
151
152 return (0);
153 }
154
155 /*
156 * Used to make a defined VOP fall back to the default VOP.
157 */
158 int
159 vop_defaultop(struct vop_generic_args *ap)
160 {
161
162 return (VOCALL(default_vnodeop_p, ap->a_desc->vdesc_offset, ap));
163 }
164
165 /*
166 * Helper function to panic on some bad VOPs in some filesystems.
167 */
168 int
169 vop_panic(struct vop_generic_args *ap)
170 {
171
172 panic("filesystem goof: vop_panic[%s]", ap->a_desc->vdesc_name);
173 }
174
175 /*
176 * vop_std<something> and vop_no<something> are default functions for use by
177 * filesystems that need the "default reasonable" implementation for a
178 * particular operation.
179 *
180 * The documentation for the operations they implement exists (if it exists)
181 * in the VOP_<SOMETHING>(9) manpage (all uppercase).
182 */
183
184 /*
185 * Default vop for filesystems that do not support name lookup
186 */
187 static int
188 vop_nolookup(ap)
189 struct vop_lookup_args /* {
190 struct vnode *a_dvp;
191 struct vnode **a_vpp;
192 struct componentname *a_cnp;
193 } */ *ap;
194 {
195
196 *ap->a_vpp = NULL;
197 return (ENOTDIR);
198 }
199
200 /*
201 * vop_nostrategy:
202 *
203 * Strategy routine for VFS devices that have none.
204 *
205 * BIO_ERROR and B_INVAL must be cleared prior to calling any strategy
206 * routine. Typically this is done for a BIO_READ strategy call.
207 * Typically B_INVAL is assumed to already be clear prior to a write
208 * and should not be cleared manually unless you just made the buffer
209 * invalid. BIO_ERROR should be cleared either way.
210 */
211
212 static int
213 vop_nostrategy (struct vop_strategy_args *ap)
214 {
215 printf("No strategy for buffer at %p\n", ap->a_bp);
216 vprint("vnode", ap->a_vp);
217 vprint("device vnode", ap->a_bp->b_vp);
218 ap->a_bp->b_ioflags |= BIO_ERROR;
219 ap->a_bp->b_error = EOPNOTSUPP;
220 bufdone(ap->a_bp);
221 return (EOPNOTSUPP);
222 }
223
224 /*
225 * vop_nospecstrategy:
226 *
227 * This shouldn't happen. VOP_SPECSTRATEGY should always have a VCHR
228 * argument vnode, and thos have a method for specstrategy over in
229 * specfs, so we only ever get here if somebody botched it.
230 * Pass the call to VOP_STRATEGY() and get on with life.
231 * The first time we print some info useful for debugging.
232 */
233
234 static int
235 vop_nospecstrategy (struct vop_specstrategy_args *ap)
236 {
237 static int once;
238
239 if (!once) {
240 vprint("VOP_SPECSTRATEGY on non-VCHR", ap->a_vp);
241 backtrace();
242 once++;
243 }
244 return VOP_STRATEGY(ap->a_vp, ap->a_bp);
245 }
246
247 /*
248 * vop_stdpathconf:
249 *
250 * Standard implementation of POSIX pathconf, to get information about limits
251 * for a filesystem.
252 * Override per filesystem for the case where the filesystem has smaller
253 * limits.
254 */
255 int
256 vop_stdpathconf(ap)
257 struct vop_pathconf_args /* {
258 struct vnode *a_vp;
259 int a_name;
260 int *a_retval;
261 } */ *ap;
262 {
263
264 switch (ap->a_name) {
265 case _PC_LINK_MAX:
266 *ap->a_retval = LINK_MAX;
267 return (0);
268 case _PC_MAX_CANON:
269 *ap->a_retval = MAX_CANON;
270 return (0);
271 case _PC_MAX_INPUT:
272 *ap->a_retval = MAX_INPUT;
273 return (0);
274 case _PC_PIPE_BUF:
275 *ap->a_retval = PIPE_BUF;
276 return (0);
277 case _PC_CHOWN_RESTRICTED:
278 *ap->a_retval = 1;
279 return (0);
280 case _PC_VDISABLE:
281 *ap->a_retval = _POSIX_VDISABLE;
282 return (0);
283 default:
284 return (EINVAL);
285 }
286 /* NOTREACHED */
287 }
288
289 /*
290 * Standard lock, unlock and islocked functions.
291 */
292 int
293 vop_stdlock(ap)
294 struct vop_lock_args /* {
295 struct vnode *a_vp;
296 int a_flags;
297 struct thread *a_td;
298 } */ *ap;
299 {
300 struct vnode *vp = ap->a_vp;
301
302 #ifndef DEBUG_LOCKS
303 return (lockmgr(vp->v_vnlock, ap->a_flags, VI_MTX(vp), ap->a_td));
304 #else
305 return (debuglockmgr(vp->v_vnlock, ap->a_flags, VI_MTX(vp),
306 ap->a_td, "vop_stdlock", vp->filename, vp->line));
307 #endif
308 }
309
310 /* See above. */
311 int
312 vop_stdunlock(ap)
313 struct vop_unlock_args /* {
314 struct vnode *a_vp;
315 int a_flags;
316 struct thread *a_td;
317 } */ *ap;
318 {
319 struct vnode *vp = ap->a_vp;
320
321 return (lockmgr(vp->v_vnlock, ap->a_flags | LK_RELEASE, VI_MTX(vp),
322 ap->a_td));
323 }
324
325 /* See above. */
326 int
327 vop_stdislocked(ap)
328 struct vop_islocked_args /* {
329 struct vnode *a_vp;
330 struct thread *a_td;
331 } */ *ap;
332 {
333
334 return (lockstatus(ap->a_vp->v_vnlock, ap->a_td));
335 }
336
337 /* Mark the vnode inactive */
338 int
339 vop_stdinactive(ap)
340 struct vop_inactive_args /* {
341 struct vnode *a_vp;
342 struct thread *a_td;
343 } */ *ap;
344 {
345
346 VOP_UNLOCK(ap->a_vp, 0, ap->a_td);
347 return (0);
348 }
349
350 /*
351 * Return true for select/poll.
352 */
353 int
354 vop_nopoll(ap)
355 struct vop_poll_args /* {
356 struct vnode *a_vp;
357 int a_events;
358 struct ucred *a_cred;
359 struct thread *a_td;
360 } */ *ap;
361 {
362 /*
363 * Return true for read/write. If the user asked for something
364 * special, return POLLNVAL, so that clients have a way of
365 * determining reliably whether or not the extended
366 * functionality is present without hard-coding knowledge
367 * of specific filesystem implementations.
368 */
369 if (ap->a_events & ~POLLSTANDARD)
370 return (POLLNVAL);
371
372 return (ap->a_events & (POLLIN | POLLOUT | POLLRDNORM | POLLWRNORM));
373 }
374
375 /*
376 * Implement poll for local filesystems that support it.
377 */
378 int
379 vop_stdpoll(ap)
380 struct vop_poll_args /* {
381 struct vnode *a_vp;
382 int a_events;
383 struct ucred *a_cred;
384 struct thread *a_td;
385 } */ *ap;
386 {
387 if (ap->a_events & ~POLLSTANDARD)
388 return (vn_pollrecord(ap->a_vp, ap->a_td, ap->a_events));
389 return (ap->a_events & (POLLIN | POLLOUT | POLLRDNORM | POLLWRNORM));
390 }
391
392 /*
393 * Stubs to use when there is no locking to be done on the underlying object.
394 * A minimal shared lock is necessary to ensure that the underlying object
395 * is not revoked while an operation is in progress. So, an active shared
396 * count is maintained in an auxillary vnode lock structure.
397 */
398 int
399 vop_sharedlock(ap)
400 struct vop_lock_args /* {
401 struct vnode *a_vp;
402 int a_flags;
403 struct thread *a_td;
404 } */ *ap;
405 {
406 /*
407 * This code cannot be used until all the non-locking filesystems
408 * (notably NFS) are converted to properly lock and release nodes.
409 * Also, certain vnode operations change the locking state within
410 * the operation (create, mknod, remove, link, rename, mkdir, rmdir,
411 * and symlink). Ideally these operations should not change the
412 * lock state, but should be changed to let the caller of the
413 * function unlock them. Otherwise all intermediate vnode layers
414 * (such as union, umapfs, etc) must catch these functions to do
415 * the necessary locking at their layer. Note that the inactive
416 * and lookup operations also change their lock state, but this
417 * cannot be avoided, so these two operations will always need
418 * to be handled in intermediate layers.
419 */
420 struct vnode *vp = ap->a_vp;
421 int vnflags, flags = ap->a_flags;
422
423 switch (flags & LK_TYPE_MASK) {
424 case LK_DRAIN:
425 vnflags = LK_DRAIN;
426 break;
427 case LK_EXCLUSIVE:
428 #ifdef DEBUG_VFS_LOCKS
429 /*
430 * Normally, we use shared locks here, but that confuses
431 * the locking assertions.
432 */
433 vnflags = LK_EXCLUSIVE;
434 break;
435 #endif
436 case LK_SHARED:
437 vnflags = LK_SHARED;
438 break;
439 case LK_UPGRADE:
440 case LK_EXCLUPGRADE:
441 case LK_DOWNGRADE:
442 return (0);
443 case LK_RELEASE:
444 default:
445 panic("vop_sharedlock: bad operation %d", flags & LK_TYPE_MASK);
446 }
447 vnflags |= flags & (LK_INTERLOCK | LK_EXTFLG_MASK);
448 #ifndef DEBUG_LOCKS
449 return (lockmgr(vp->v_vnlock, vnflags, VI_MTX(vp), ap->a_td));
450 #else
451 return (debuglockmgr(vp->v_vnlock, vnflags, VI_MTX(vp), ap->a_td,
452 "vop_sharedlock", vp->filename, vp->line));
453 #endif
454 }
455
456 /*
457 * Stubs to use when there is no locking to be done on the underlying object.
458 * A minimal shared lock is necessary to ensure that the underlying object
459 * is not revoked while an operation is in progress. So, an active shared
460 * count is maintained in an auxillary vnode lock structure.
461 */
462 int
463 vop_nolock(ap)
464 struct vop_lock_args /* {
465 struct vnode *a_vp;
466 int a_flags;
467 struct thread *a_td;
468 } */ *ap;
469 {
470 #ifdef notyet
471 /*
472 * This code cannot be used until all the non-locking filesystems
473 * (notably NFS) are converted to properly lock and release nodes.
474 * Also, certain vnode operations change the locking state within
475 * the operation (create, mknod, remove, link, rename, mkdir, rmdir,
476 * and symlink). Ideally these operations should not change the
477 * lock state, but should be changed to let the caller of the
478 * function unlock them. Otherwise all intermediate vnode layers
479 * (such as union, umapfs, etc) must catch these functions to do
480 * the necessary locking at their layer. Note that the inactive
481 * and lookup operations also change their lock state, but this
482 * cannot be avoided, so these two operations will always need
483 * to be handled in intermediate layers.
484 */
485 struct vnode *vp = ap->a_vp;
486 int vnflags, flags = ap->a_flags;
487
488 switch (flags & LK_TYPE_MASK) {
489 case LK_DRAIN:
490 vnflags = LK_DRAIN;
491 break;
492 case LK_EXCLUSIVE:
493 case LK_SHARED:
494 vnflags = LK_SHARED;
495 break;
496 case LK_UPGRADE:
497 case LK_EXCLUPGRADE:
498 case LK_DOWNGRADE:
499 return (0);
500 case LK_RELEASE:
501 default:
502 panic("vop_nolock: bad operation %d", flags & LK_TYPE_MASK);
503 }
504 vnflags |= flags & (LK_INTERLOCK | LK_EXTFLG_MASK);
505 return(lockmgr(vp->v_vnlock, vnflags, VI_MTX(vp), ap->a_td));
506 #else /* for now */
507 /*
508 * Since we are not using the lock manager, we must clear
509 * the interlock here.
510 */
511 if (ap->a_flags & LK_INTERLOCK)
512 VI_UNLOCK(ap->a_vp);
513 return (0);
514 #endif
515 }
516
517 /*
518 * Do the inverse of vop_nolock, handling the interlock in a compatible way.
519 */
520 int
521 vop_nounlock(ap)
522 struct vop_unlock_args /* {
523 struct vnode *a_vp;
524 int a_flags;
525 struct thread *a_td;
526 } */ *ap;
527 {
528
529 /*
530 * Since we are not using the lock manager, we must clear
531 * the interlock here.
532 */
533 if (ap->a_flags & LK_INTERLOCK)
534 VI_UNLOCK(ap->a_vp);
535 return (0);
536 }
537
538 /*
539 * Return whether or not the node is in use.
540 */
541 int
542 vop_noislocked(ap)
543 struct vop_islocked_args /* {
544 struct vnode *a_vp;
545 struct thread *a_td;
546 } */ *ap;
547 {
548
549 return (0);
550 }
551
552 /*
553 * Return our mount point, as we will take charge of the writes.
554 */
555 int
556 vop_stdgetwritemount(ap)
557 struct vop_getwritemount_args /* {
558 struct vnode *a_vp;
559 struct mount **a_mpp;
560 } */ *ap;
561 {
562
563 *(ap->a_mpp) = ap->a_vp->v_mount;
564 return (0);
565 }
566
567 /* Create the VM system backing object for this vnode */
568 int
569 vop_stdcreatevobject(ap)
570 struct vop_createvobject_args /* {
571 struct vnode *vp;
572 struct ucred *cred;
573 struct thread *td;
574 } */ *ap;
575 {
576 struct vnode *vp = ap->a_vp;
577 struct ucred *cred = ap->a_cred;
578 struct thread *td = ap->a_td;
579 struct vattr vat;
580 vm_object_t object;
581 int error = 0;
582
583 GIANT_REQUIRED;
584
585 if (!vn_isdisk(vp, NULL) && vn_canvmio(vp) == FALSE)
586 return (0);
587
588 retry:
589 if ((object = vp->v_object) == NULL) {
590 if (vp->v_type == VREG || vp->v_type == VDIR) {
591 if ((error = VOP_GETATTR(vp, &vat, cred, td)) != 0)
592 goto retn;
593 object = vnode_pager_alloc(vp, vat.va_size, 0, 0);
594 } else if (devsw(vp->v_rdev) != NULL) {
595 /*
596 * This simply allocates the biggest object possible
597 * for a disk vnode. This should be fixed, but doesn't
598 * cause any problems (yet).
599 */
600 object = vnode_pager_alloc(vp, IDX_TO_OFF(INT_MAX), 0, 0);
601 } else {
602 goto retn;
603 }
604 /*
605 * Dereference the reference we just created. This assumes
606 * that the object is associated with the vp.
607 */
608 VM_OBJECT_LOCK(object);
609 object->ref_count--;
610 VM_OBJECT_UNLOCK(object);
611 vrele(vp);
612 } else {
613 VM_OBJECT_LOCK(object);
614 if (object->flags & OBJ_DEAD) {
615 VOP_UNLOCK(vp, 0, td);
616 msleep(object, VM_OBJECT_MTX(object), PDROP | PVM,
617 "vodead", 0);
618 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, td);
619 goto retry;
620 }
621 VM_OBJECT_UNLOCK(object);
622 }
623
624 KASSERT(vp->v_object != NULL, ("vfs_object_create: NULL object"));
625 vp->v_vflag |= VV_OBJBUF;
626
627 retn:
628 return (error);
629 }
630
631 /* Destroy the VM system object associated with this vnode */
632 int
633 vop_stddestroyvobject(ap)
634 struct vop_destroyvobject_args /* {
635 struct vnode *vp;
636 } */ *ap;
637 {
638 struct vnode *vp = ap->a_vp;
639 vm_object_t obj = vp->v_object;
640
641 GIANT_REQUIRED;
642
643 if (obj == NULL)
644 return (0);
645 VM_OBJECT_LOCK(obj);
646 if (obj->ref_count == 0) {
647 /*
648 * vclean() may be called twice. The first time
649 * removes the primary reference to the object,
650 * the second time goes one further and is a
651 * special-case to terminate the object.
652 *
653 * don't double-terminate the object
654 */
655 if ((obj->flags & OBJ_DEAD) == 0)
656 vm_object_terminate(obj);
657 else
658 VM_OBJECT_UNLOCK(obj);
659 } else {
660 /*
661 * Woe to the process that tries to page now :-).
662 */
663 vm_pager_deallocate(obj);
664 VM_OBJECT_UNLOCK(obj);
665 }
666 return (0);
667 }
668
669 /*
670 * Return the underlying VM object. This routine may be called with or
671 * without the vnode interlock held. If called without, the returned
672 * object is not guarenteed to be valid. The syncer typically gets the
673 * object without holding the interlock in order to quickly test whether
674 * it might be dirty before going heavy-weight. vm_object's use zalloc
675 * and thus stable-storage, so this is safe.
676 */
677 int
678 vop_stdgetvobject(ap)
679 struct vop_getvobject_args /* {
680 struct vnode *vp;
681 struct vm_object **objpp;
682 } */ *ap;
683 {
684 struct vnode *vp = ap->a_vp;
685 struct vm_object **objpp = ap->a_objpp;
686
687 if (objpp)
688 *objpp = vp->v_object;
689 return (vp->v_object ? 0 : EINVAL);
690 }
691
692 /* XXX Needs good comment and VOP_BMAP(9) manpage */
693 int
694 vop_stdbmap(ap)
695 struct vop_bmap_args /* {
696 struct vnode *a_vp;
697 daddr_t a_bn;
698 struct vnode **a_vpp;
699 daddr_t *a_bnp;
700 int *a_runp;
701 int *a_runb;
702 } */ *ap;
703 {
704
705 if (ap->a_vpp != NULL)
706 *ap->a_vpp = ap->a_vp;
707 if (ap->a_bnp != NULL)
708 *ap->a_bnp = ap->a_bn * btodb(ap->a_vp->v_mount->mnt_stat.f_iosize);
709 if (ap->a_runp != NULL)
710 *ap->a_runp = 0;
711 if (ap->a_runb != NULL)
712 *ap->a_runb = 0;
713 return (0);
714 }
715
716 int
717 vop_stdfsync(ap)
718 struct vop_fsync_args /* {
719 struct vnode *a_vp;
720 struct ucred *a_cred;
721 int a_waitfor;
722 struct thread *a_td;
723 } */ *ap;
724 {
725 struct vnode *vp = ap->a_vp;
726 struct buf *bp;
727 struct buf *nbp;
728 int s, error = 0;
729 int maxretry = 100; /* large, arbitrarily chosen */
730
731 VI_LOCK(vp);
732 loop1:
733 /*
734 * MARK/SCAN initialization to avoid infinite loops.
735 */
736 s = splbio();
737 TAILQ_FOREACH(bp, &vp->v_dirtyblkhd, b_vnbufs) {
738 bp->b_vflags &= ~BV_SCANNED;
739 bp->b_error = 0;
740 }
741 splx(s);
742
743 /*
744 * Flush all dirty buffers associated with a block device.
745 */
746 loop2:
747 s = splbio();
748 for (bp = TAILQ_FIRST(&vp->v_dirtyblkhd); bp != NULL; bp = nbp) {
749 nbp = TAILQ_NEXT(bp, b_vnbufs);
750 if ((bp->b_vflags & BV_SCANNED) != 0)
751 continue;
752 bp->b_vflags |= BV_SCANNED;
753 if (BUF_LOCK(bp, LK_EXCLUSIVE | LK_NOWAIT, NULL))
754 continue;
755 VI_UNLOCK(vp);
756 if ((bp->b_flags & B_DELWRI) == 0)
757 panic("fsync: not dirty");
758 if ((vp->v_vflag & VV_OBJBUF) && (bp->b_flags & B_CLUSTEROK)) {
759 vfs_bio_awrite(bp);
760 splx(s);
761 } else {
762 bremfree(bp);
763 splx(s);
764 bawrite(bp);
765 }
766 VI_LOCK(vp);
767 goto loop2;
768 }
769
770 /*
771 * If synchronous the caller expects us to completely resolve all
772 * dirty buffers in the system. Wait for in-progress I/O to
773 * complete (which could include background bitmap writes), then
774 * retry if dirty blocks still exist.
775 */
776 if (ap->a_waitfor == MNT_WAIT) {
777 while (vp->v_numoutput) {
778 vp->v_iflag |= VI_BWAIT;
779 msleep((caddr_t)&vp->v_numoutput, VI_MTX(vp),
780 PRIBIO + 1, "fsync", 0);
781 }
782 if (!TAILQ_EMPTY(&vp->v_dirtyblkhd)) {
783 /*
784 * If we are unable to write any of these buffers
785 * then we fail now rather than trying endlessly
786 * to write them out.
787 */
788 TAILQ_FOREACH(bp, &vp->v_dirtyblkhd, b_vnbufs)
789 if ((error = bp->b_error) == 0)
790 continue;
791 if (error == 0 && --maxretry >= 0) {
792 splx(s);
793 goto loop1;
794 }
795 vprint("fsync: giving up on dirty", vp);
796 error = EAGAIN;
797 }
798 }
799 VI_UNLOCK(vp);
800 splx(s);
801
802 return (error);
803 }
804
805 /* XXX Needs good comment and more info in the manpage (VOP_GETPAGES(9)). */
806 int
807 vop_stdgetpages(ap)
808 struct vop_getpages_args /* {
809 struct vnode *a_vp;
810 vm_page_t *a_m;
811 int a_count;
812 int a_reqpage;
813 vm_ooffset_t a_offset;
814 } */ *ap;
815 {
816
817 return vnode_pager_generic_getpages(ap->a_vp, ap->a_m,
818 ap->a_count, ap->a_reqpage);
819 }
820
821 /* XXX Needs good comment and more info in the manpage (VOP_PUTPAGES(9)). */
822 int
823 vop_stdputpages(ap)
824 struct vop_putpages_args /* {
825 struct vnode *a_vp;
826 vm_page_t *a_m;
827 int a_count;
828 int a_sync;
829 int *a_rtvals;
830 vm_ooffset_t a_offset;
831 } */ *ap;
832 {
833
834 return vnode_pager_generic_putpages(ap->a_vp, ap->a_m, ap->a_count,
835 ap->a_sync, ap->a_rtvals);
836 }
837
838 /*
839 * vfs default ops
840 * used to fill the vfs function table to get reasonable default return values.
841 */
842 int
843 vfs_stdroot (mp, vpp)
844 struct mount *mp;
845 struct vnode **vpp;
846 {
847 return (EOPNOTSUPP);
848 }
849
850 int
851 vfs_stdstatfs (mp, sbp, td)
852 struct mount *mp;
853 struct statfs *sbp;
854 struct thread *td;
855 {
856 return (EOPNOTSUPP);
857 }
858
859 int
860 vfs_stdvptofh (vp, fhp)
861 struct vnode *vp;
862 struct fid *fhp;
863 {
864 return (EOPNOTSUPP);
865 }
866
867 int
868 vfs_stdstart (mp, flags, td)
869 struct mount *mp;
870 int flags;
871 struct thread *td;
872 {
873 return (0);
874 }
875
876 int
877 vfs_stdquotactl (mp, cmds, uid, arg, td)
878 struct mount *mp;
879 int cmds;
880 uid_t uid;
881 caddr_t arg;
882 struct thread *td;
883 {
884 return (EOPNOTSUPP);
885 }
886
887 int
888 vfs_stdsync(mp, waitfor, cred, td)
889 struct mount *mp;
890 int waitfor;
891 struct ucred *cred;
892 struct thread *td;
893 {
894 struct vnode *vp, *nvp;
895 int error, lockreq, allerror = 0;
896
897 lockreq = LK_EXCLUSIVE | LK_INTERLOCK;
898 if (waitfor != MNT_WAIT)
899 lockreq |= LK_NOWAIT;
900 /*
901 * Force stale buffer cache information to be flushed.
902 */
903 mtx_lock(&mntvnode_mtx);
904 loop:
905 for (vp = TAILQ_FIRST(&mp->mnt_nvnodelist); vp != NULL; vp = nvp) {
906 /*
907 * If the vnode that we are about to sync is no longer
908 * associated with this mount point, start over.
909 */
910 if (vp->v_mount != mp)
911 goto loop;
912
913 nvp = TAILQ_NEXT(vp, v_nmntvnodes);
914
915 VI_LOCK(vp);
916 if (TAILQ_EMPTY(&vp->v_dirtyblkhd)) {
917 VI_UNLOCK(vp);
918 continue;
919 }
920 mtx_unlock(&mntvnode_mtx);
921
922 if ((error = vget(vp, lockreq, td)) != 0) {
923 if (error == ENOENT)
924 goto loop;
925 continue;
926 }
927 error = VOP_FSYNC(vp, cred, waitfor, td);
928 if (error)
929 allerror = error;
930
931 mtx_lock(&mntvnode_mtx);
932 if (nvp != TAILQ_NEXT(vp, v_nmntvnodes)) {
933 vput(vp);
934 goto loop;
935 }
936 vput(vp);
937 }
938 mtx_unlock(&mntvnode_mtx);
939 return (allerror);
940 }
941
942 int
943 vfs_stdnosync (mp, waitfor, cred, td)
944 struct mount *mp;
945 int waitfor;
946 struct ucred *cred;
947 struct thread *td;
948 {
949 return (0);
950 }
951
952 int
953 vfs_stdvget (mp, ino, flags, vpp)
954 struct mount *mp;
955 ino_t ino;
956 int flags;
957 struct vnode **vpp;
958 {
959 return (EOPNOTSUPP);
960 }
961
962 int
963 vfs_stdfhtovp (mp, fhp, vpp)
964 struct mount *mp;
965 struct fid *fhp;
966 struct vnode **vpp;
967 {
968 return (EOPNOTSUPP);
969 }
970
971 int
972 vfs_stdinit (vfsp)
973 struct vfsconf *vfsp;
974 {
975 return (0);
976 }
977
978 int
979 vfs_stduninit (vfsp)
980 struct vfsconf *vfsp;
981 {
982 return(0);
983 }
984
985 int
986 vfs_stdextattrctl(mp, cmd, filename_vp, attrnamespace, attrname, td)
987 struct mount *mp;
988 int cmd;
989 struct vnode *filename_vp;
990 int attrnamespace;
991 const char *attrname;
992 struct thread *td;
993 {
994 if (filename_vp != NULL)
995 VOP_UNLOCK(filename_vp, 0, td);
996 return(EOPNOTSUPP);
997 }
998
999 /* end of vfs default ops */
Cache object: 375a73023dee2b9a6c9c105c3295f6a8
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