FreeBSD/Linux Kernel Cross Reference
sys/kern/vfs_subr.c
1 /*
2 * Copyright (c) 1989, 1993
3 * The Regents of the University of California. All rights reserved.
4 * (c) UNIX System Laboratories, Inc.
5 * All or some portions of this file are derived from material licensed
6 * to the University of California by American Telephone and Telegraph
7 * Co. or Unix System Laboratories, Inc. and are reproduced herein with
8 * the permission of UNIX System Laboratories, Inc.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 * 3. Neither the name of the University nor the names of its contributors
19 * may be used to endorse or promote products derived from this software
20 * without specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * SUCH DAMAGE.
33 *
34 * @(#)vfs_subr.c 8.31 (Berkeley) 5/26/95
35 * $FreeBSD: src/sys/kern/vfs_subr.c,v 1.249.2.30 2003/04/04 20:35:57 tegge Exp $
36 */
37
38 /*
39 * External virtual filesystem routines
40 */
41 #include "opt_ddb.h"
42
43 #include <sys/param.h>
44 #include <sys/systm.h>
45 #include <sys/buf.h>
46 #include <sys/conf.h>
47 #include <sys/dirent.h>
48 #include <sys/domain.h>
49 #include <sys/eventhandler.h>
50 #include <sys/fcntl.h>
51 #include <sys/file.h>
52 #include <sys/kernel.h>
53 #include <sys/kthread.h>
54 #include <sys/malloc.h>
55 #include <sys/mbuf.h>
56 #include <sys/mount.h>
57 #include <sys/priv.h>
58 #include <sys/proc.h>
59 #include <sys/reboot.h>
60 #include <sys/socket.h>
61 #include <sys/stat.h>
62 #include <sys/sysctl.h>
63 #include <sys/syslog.h>
64 #include <sys/unistd.h>
65 #include <sys/vmmeter.h>
66 #include <sys/vnode.h>
67
68 #include <machine/limits.h>
69
70 #include <vm/vm.h>
71 #include <vm/vm_object.h>
72 #include <vm/vm_extern.h>
73 #include <vm/vm_kern.h>
74 #include <vm/pmap.h>
75 #include <vm/vm_map.h>
76 #include <vm/vm_page.h>
77 #include <vm/vm_pager.h>
78 #include <vm/vnode_pager.h>
79 #include <vm/vm_zone.h>
80
81 #include <sys/buf2.h>
82 #include <sys/thread2.h>
83 #include <sys/sysref2.h>
84 #include <sys/mplock2.h>
85
86 static MALLOC_DEFINE(M_NETADDR, "Export Host", "Export host address structure");
87
88 int numvnodes;
89 SYSCTL_INT(_debug, OID_AUTO, numvnodes, CTLFLAG_RD, &numvnodes, 0,
90 "Number of vnodes allocated");
91 int verbose_reclaims;
92 SYSCTL_INT(_debug, OID_AUTO, verbose_reclaims, CTLFLAG_RD, &verbose_reclaims, 0,
93 "Output filename of reclaimed vnode(s)");
94
95 enum vtype iftovt_tab[16] = {
96 VNON, VFIFO, VCHR, VNON, VDIR, VNON, VBLK, VNON,
97 VREG, VNON, VLNK, VNON, VSOCK, VNON, VNON, VBAD,
98 };
99 int vttoif_tab[9] = {
100 0, S_IFREG, S_IFDIR, S_IFBLK, S_IFCHR, S_IFLNK,
101 S_IFSOCK, S_IFIFO, S_IFMT,
102 };
103
104 static int reassignbufcalls;
105 SYSCTL_INT(_vfs, OID_AUTO, reassignbufcalls, CTLFLAG_RW, &reassignbufcalls,
106 0, "Number of times buffers have been reassigned to the proper list");
107
108 static int check_buf_overlap = 2; /* invasive check */
109 SYSCTL_INT(_vfs, OID_AUTO, check_buf_overlap, CTLFLAG_RW, &check_buf_overlap,
110 0, "Enable overlapping buffer checks");
111
112 int nfs_mount_type = -1;
113 static struct lwkt_token spechash_token;
114 struct nfs_public nfs_pub; /* publicly exported FS */
115
116 int desiredvnodes;
117 SYSCTL_INT(_kern, KERN_MAXVNODES, maxvnodes, CTLFLAG_RW,
118 &desiredvnodes, 0, "Maximum number of vnodes");
119
120 static void vfs_free_addrlist (struct netexport *nep);
121 static int vfs_free_netcred (struct radix_node *rn, void *w);
122 static int vfs_hang_addrlist (struct mount *mp, struct netexport *nep,
123 const struct export_args *argp);
124
125 /*
126 * Red black tree functions
127 */
128 static int rb_buf_compare(struct buf *b1, struct buf *b2);
129 RB_GENERATE2(buf_rb_tree, buf, b_rbnode, rb_buf_compare, off_t, b_loffset);
130 RB_GENERATE2(buf_rb_hash, buf, b_rbhash, rb_buf_compare, off_t, b_loffset);
131
132 static int
133 rb_buf_compare(struct buf *b1, struct buf *b2)
134 {
135 if (b1->b_loffset < b2->b_loffset)
136 return(-1);
137 if (b1->b_loffset > b2->b_loffset)
138 return(1);
139 return(0);
140 }
141
142 /*
143 * Initialize the vnode management data structures.
144 *
145 * Called from vfsinit()
146 */
147 void
148 vfs_subr_init(void)
149 {
150 int factor1;
151 int factor2;
152
153 /*
154 * Desiredvnodes is kern.maxvnodes. We want to scale it
155 * according to available system memory but we may also have
156 * to limit it based on available KVM, which is capped on 32 bit
157 * systems, to ~80K vnodes or so.
158 *
159 * WARNING! For machines with 64-256M of ram we have to be sure
160 * that the default limit scales down well due to HAMMER
161 * taking up significantly more memory per-vnode vs UFS.
162 * We want around ~5800 on a 128M machine.
163 */
164 factor1 = 20 * (sizeof(struct vm_object) + sizeof(struct vnode));
165 factor2 = 25 * (sizeof(struct vm_object) + sizeof(struct vnode));
166 desiredvnodes =
167 imin((int64_t)vmstats.v_page_count * PAGE_SIZE / factor1,
168 KvaSize / factor2);
169 desiredvnodes = imax(desiredvnodes, maxproc * 8);
170
171 lwkt_token_init(&spechash_token, "spechash");
172 }
173
174 /*
175 * Knob to control the precision of file timestamps:
176 *
177 * 0 = seconds only; nanoseconds zeroed.
178 * 1 = seconds and nanoseconds, accurate within 1/HZ.
179 * 2 = seconds and nanoseconds, truncated to microseconds.
180 * >=3 = seconds and nanoseconds, maximum precision.
181 */
182 enum { TSP_SEC, TSP_HZ, TSP_USEC, TSP_NSEC };
183
184 static int timestamp_precision = TSP_SEC;
185 SYSCTL_INT(_vfs, OID_AUTO, timestamp_precision, CTLFLAG_RW,
186 ×tamp_precision, 0, "Precision of file timestamps");
187
188 /*
189 * Get a current timestamp.
190 *
191 * MPSAFE
192 */
193 void
194 vfs_timestamp(struct timespec *tsp)
195 {
196 struct timeval tv;
197
198 switch (timestamp_precision) {
199 case TSP_SEC:
200 tsp->tv_sec = time_second;
201 tsp->tv_nsec = 0;
202 break;
203 case TSP_HZ:
204 getnanotime(tsp);
205 break;
206 case TSP_USEC:
207 microtime(&tv);
208 TIMEVAL_TO_TIMESPEC(&tv, tsp);
209 break;
210 case TSP_NSEC:
211 default:
212 nanotime(tsp);
213 break;
214 }
215 }
216
217 /*
218 * Set vnode attributes to VNOVAL
219 */
220 void
221 vattr_null(struct vattr *vap)
222 {
223 vap->va_type = VNON;
224 vap->va_size = VNOVAL;
225 vap->va_bytes = VNOVAL;
226 vap->va_mode = VNOVAL;
227 vap->va_nlink = VNOVAL;
228 vap->va_uid = VNOVAL;
229 vap->va_gid = VNOVAL;
230 vap->va_fsid = VNOVAL;
231 vap->va_fileid = VNOVAL;
232 vap->va_blocksize = VNOVAL;
233 vap->va_rmajor = VNOVAL;
234 vap->va_rminor = VNOVAL;
235 vap->va_atime.tv_sec = VNOVAL;
236 vap->va_atime.tv_nsec = VNOVAL;
237 vap->va_mtime.tv_sec = VNOVAL;
238 vap->va_mtime.tv_nsec = VNOVAL;
239 vap->va_ctime.tv_sec = VNOVAL;
240 vap->va_ctime.tv_nsec = VNOVAL;
241 vap->va_flags = VNOVAL;
242 vap->va_gen = VNOVAL;
243 vap->va_vaflags = 0;
244 /* va_*_uuid fields are only valid if related flags are set */
245 }
246
247 /*
248 * Flush out and invalidate all buffers associated with a vnode.
249 *
250 * vp must be locked.
251 */
252 static int vinvalbuf_bp(struct buf *bp, void *data);
253
254 struct vinvalbuf_bp_info {
255 struct vnode *vp;
256 int slptimeo;
257 int lkflags;
258 int flags;
259 int clean;
260 };
261
262 int
263 vinvalbuf(struct vnode *vp, int flags, int slpflag, int slptimeo)
264 {
265 struct vinvalbuf_bp_info info;
266 vm_object_t object;
267 int error;
268
269 lwkt_gettoken(&vp->v_token);
270
271 /*
272 * If we are being asked to save, call fsync to ensure that the inode
273 * is updated.
274 */
275 if (flags & V_SAVE) {
276 error = bio_track_wait(&vp->v_track_write, slpflag, slptimeo);
277 if (error)
278 goto done;
279 if (!RB_EMPTY(&vp->v_rbdirty_tree)) {
280 if ((error = VOP_FSYNC(vp, MNT_WAIT, 0)) != 0)
281 goto done;
282 #if 0
283 /*
284 * Dirty bufs may be left or generated via races
285 * in circumstances where vinvalbuf() is called on
286 * a vnode not undergoing reclamation. Only
287 * panic if we are trying to reclaim the vnode.
288 */
289 if ((vp->v_flag & VRECLAIMED) &&
290 (bio_track_active(&vp->v_track_write) ||
291 !RB_EMPTY(&vp->v_rbdirty_tree))) {
292 panic("vinvalbuf: dirty bufs");
293 }
294 #endif
295 }
296 }
297 info.slptimeo = slptimeo;
298 info.lkflags = LK_EXCLUSIVE | LK_SLEEPFAIL;
299 if (slpflag & PCATCH)
300 info.lkflags |= LK_PCATCH;
301 info.flags = flags;
302 info.vp = vp;
303
304 /*
305 * Flush the buffer cache until nothing is left, wait for all I/O
306 * to complete. At least one pass is required. We might block
307 * in the pip code so we have to re-check. Order is important.
308 */
309 do {
310 /*
311 * Flush buffer cache
312 */
313 if (!RB_EMPTY(&vp->v_rbclean_tree)) {
314 info.clean = 1;
315 error = RB_SCAN(buf_rb_tree, &vp->v_rbclean_tree,
316 NULL, vinvalbuf_bp, &info);
317 }
318 if (!RB_EMPTY(&vp->v_rbdirty_tree)) {
319 info.clean = 0;
320 error = RB_SCAN(buf_rb_tree, &vp->v_rbdirty_tree,
321 NULL, vinvalbuf_bp, &info);
322 }
323
324 /*
325 * Wait for I/O completion.
326 */
327 bio_track_wait(&vp->v_track_write, 0, 0);
328 if ((object = vp->v_object) != NULL)
329 refcount_wait(&object->paging_in_progress, "vnvlbx");
330 } while (bio_track_active(&vp->v_track_write) ||
331 !RB_EMPTY(&vp->v_rbclean_tree) ||
332 !RB_EMPTY(&vp->v_rbdirty_tree));
333
334 /*
335 * Destroy the copy in the VM cache, too.
336 */
337 if ((object = vp->v_object) != NULL) {
338 vm_object_page_remove(object, 0, 0,
339 (flags & V_SAVE) ? TRUE : FALSE);
340 }
341
342 if (!RB_EMPTY(&vp->v_rbdirty_tree) || !RB_EMPTY(&vp->v_rbclean_tree))
343 panic("vinvalbuf: flush failed");
344 if (!RB_EMPTY(&vp->v_rbhash_tree))
345 panic("vinvalbuf: flush failed, buffers still present");
346 error = 0;
347 done:
348 lwkt_reltoken(&vp->v_token);
349 return (error);
350 }
351
352 static int
353 vinvalbuf_bp(struct buf *bp, void *data)
354 {
355 struct vinvalbuf_bp_info *info = data;
356 int error;
357
358 if (BUF_LOCK(bp, LK_EXCLUSIVE | LK_NOWAIT)) {
359 atomic_add_int(&bp->b_refs, 1);
360 error = BUF_TIMELOCK(bp, info->lkflags,
361 "vinvalbuf", info->slptimeo);
362 atomic_subtract_int(&bp->b_refs, 1);
363 if (error == 0) {
364 BUF_UNLOCK(bp);
365 error = ENOLCK;
366 }
367 if (error == ENOLCK)
368 return(0);
369 return (-error);
370 }
371 KKASSERT(bp->b_vp == info->vp);
372
373 /*
374 * Must check clean/dirty status after successfully locking as
375 * it may race.
376 */
377 if ((info->clean && (bp->b_flags & B_DELWRI)) ||
378 (info->clean == 0 && (bp->b_flags & B_DELWRI) == 0)) {
379 BUF_UNLOCK(bp);
380 return(0);
381 }
382
383 /*
384 * NOTE: NO B_LOCKED CHECK. Also no buf_checkwrite()
385 * check. This code will write out the buffer, period.
386 */
387 bremfree(bp);
388 if (((bp->b_flags & (B_DELWRI | B_INVAL)) == B_DELWRI) &&
389 (info->flags & V_SAVE)) {
390 cluster_awrite(bp);
391 } else if (info->flags & V_SAVE) {
392 /*
393 * Cannot set B_NOCACHE on a clean buffer as this will
394 * destroy the VM backing store which might actually
395 * be dirty (and unsynchronized).
396 */
397 bp->b_flags |= (B_INVAL | B_RELBUF);
398 brelse(bp);
399 } else {
400 bp->b_flags |= (B_INVAL | B_NOCACHE | B_RELBUF);
401 brelse(bp);
402 }
403 return(0);
404 }
405
406 /*
407 * Truncate a file's buffer and pages to a specified length. This
408 * is in lieu of the old vinvalbuf mechanism, which performed unneeded
409 * sync activity.
410 *
411 * The vnode must be locked.
412 */
413 static int vtruncbuf_bp_trunc_cmp(struct buf *bp, void *data);
414 static int vtruncbuf_bp_trunc(struct buf *bp, void *data);
415 static int vtruncbuf_bp_metasync_cmp(struct buf *bp, void *data);
416 static int vtruncbuf_bp_metasync(struct buf *bp, void *data);
417
418 struct vtruncbuf_info {
419 struct vnode *vp;
420 off_t truncloffset;
421 int clean;
422 };
423
424 int
425 vtruncbuf(struct vnode *vp, off_t length, int blksize)
426 {
427 struct vtruncbuf_info info;
428 const char *filename;
429 int count;
430
431 /*
432 * Round up to the *next* block, then destroy the buffers in question.
433 * Since we are only removing some of the buffers we must rely on the
434 * scan count to determine whether a loop is necessary.
435 */
436 if ((count = (int)(length % blksize)) != 0)
437 info.truncloffset = length + (blksize - count);
438 else
439 info.truncloffset = length;
440 info.vp = vp;
441
442 lwkt_gettoken(&vp->v_token);
443 do {
444 info.clean = 1;
445 count = RB_SCAN(buf_rb_tree, &vp->v_rbclean_tree,
446 vtruncbuf_bp_trunc_cmp,
447 vtruncbuf_bp_trunc, &info);
448 info.clean = 0;
449 count += RB_SCAN(buf_rb_tree, &vp->v_rbdirty_tree,
450 vtruncbuf_bp_trunc_cmp,
451 vtruncbuf_bp_trunc, &info);
452 } while(count);
453
454 /*
455 * For safety, fsync any remaining metadata if the file is not being
456 * truncated to 0. Since the metadata does not represent the entire
457 * dirty list we have to rely on the hit count to ensure that we get
458 * all of it.
459 */
460 if (length > 0) {
461 do {
462 count = RB_SCAN(buf_rb_tree, &vp->v_rbdirty_tree,
463 vtruncbuf_bp_metasync_cmp,
464 vtruncbuf_bp_metasync, &info);
465 } while (count);
466 }
467
468 /*
469 * Clean out any left over VM backing store.
470 *
471 * It is possible to have in-progress I/O from buffers that were
472 * not part of the truncation. This should not happen if we
473 * are truncating to 0-length.
474 */
475 vnode_pager_setsize(vp, length);
476 bio_track_wait(&vp->v_track_write, 0, 0);
477
478 /*
479 * Debugging only
480 */
481 spin_lock(&vp->v_spin);
482 filename = TAILQ_FIRST(&vp->v_namecache) ?
483 TAILQ_FIRST(&vp->v_namecache)->nc_name : "?";
484 spin_unlock(&vp->v_spin);
485
486 /*
487 * Make sure no buffers were instantiated while we were trying
488 * to clean out the remaining VM pages. This could occur due
489 * to busy dirty VM pages being flushed out to disk.
490 */
491 do {
492 info.clean = 1;
493 count = RB_SCAN(buf_rb_tree, &vp->v_rbclean_tree,
494 vtruncbuf_bp_trunc_cmp,
495 vtruncbuf_bp_trunc, &info);
496 info.clean = 0;
497 count += RB_SCAN(buf_rb_tree, &vp->v_rbdirty_tree,
498 vtruncbuf_bp_trunc_cmp,
499 vtruncbuf_bp_trunc, &info);
500 if (count) {
501 kprintf("Warning: vtruncbuf(): Had to re-clean %d "
502 "left over buffers in %s\n", count, filename);
503 }
504 } while(count);
505
506 lwkt_reltoken(&vp->v_token);
507
508 return (0);
509 }
510
511 /*
512 * The callback buffer is beyond the new file EOF and must be destroyed.
513 * Note that the compare function must conform to the RB_SCAN's requirements.
514 */
515 static
516 int
517 vtruncbuf_bp_trunc_cmp(struct buf *bp, void *data)
518 {
519 struct vtruncbuf_info *info = data;
520
521 if (bp->b_loffset >= info->truncloffset)
522 return(0);
523 return(-1);
524 }
525
526 static
527 int
528 vtruncbuf_bp_trunc(struct buf *bp, void *data)
529 {
530 struct vtruncbuf_info *info = data;
531
532 /*
533 * Do not try to use a buffer we cannot immediately lock, but sleep
534 * anyway to prevent a livelock. The code will loop until all buffers
535 * can be acted upon.
536 *
537 * We must always revalidate the buffer after locking it to deal
538 * with MP races.
539 */
540 if (BUF_LOCK(bp, LK_EXCLUSIVE | LK_NOWAIT)) {
541 atomic_add_int(&bp->b_refs, 1);
542 if (BUF_LOCK(bp, LK_EXCLUSIVE|LK_SLEEPFAIL) == 0)
543 BUF_UNLOCK(bp);
544 atomic_subtract_int(&bp->b_refs, 1);
545 } else if ((info->clean && (bp->b_flags & B_DELWRI)) ||
546 (info->clean == 0 && (bp->b_flags & B_DELWRI) == 0) ||
547 bp->b_vp != info->vp ||
548 vtruncbuf_bp_trunc_cmp(bp, data)) {
549 BUF_UNLOCK(bp);
550 } else {
551 bremfree(bp);
552 bp->b_flags |= (B_INVAL | B_RELBUF | B_NOCACHE);
553 brelse(bp);
554 }
555 return(1);
556 }
557
558 /*
559 * Fsync all meta-data after truncating a file to be non-zero. Only metadata
560 * blocks (with a negative loffset) are scanned.
561 * Note that the compare function must conform to the RB_SCAN's requirements.
562 */
563 static int
564 vtruncbuf_bp_metasync_cmp(struct buf *bp, void *data __unused)
565 {
566 if (bp->b_loffset < 0)
567 return(0);
568 return(1);
569 }
570
571 static int
572 vtruncbuf_bp_metasync(struct buf *bp, void *data)
573 {
574 struct vtruncbuf_info *info = data;
575
576 if (BUF_LOCK(bp, LK_EXCLUSIVE | LK_NOWAIT)) {
577 atomic_add_int(&bp->b_refs, 1);
578 if (BUF_LOCK(bp, LK_EXCLUSIVE|LK_SLEEPFAIL) == 0)
579 BUF_UNLOCK(bp);
580 atomic_subtract_int(&bp->b_refs, 1);
581 } else if ((bp->b_flags & B_DELWRI) == 0 ||
582 bp->b_vp != info->vp ||
583 vtruncbuf_bp_metasync_cmp(bp, data)) {
584 BUF_UNLOCK(bp);
585 } else {
586 bremfree(bp);
587 if (bp->b_vp == info->vp)
588 bawrite(bp);
589 else
590 bwrite(bp);
591 }
592 return(1);
593 }
594
595 /*
596 * vfsync - implements a multipass fsync on a file which understands
597 * dependancies and meta-data. The passed vnode must be locked. The
598 * waitfor argument may be MNT_WAIT or MNT_NOWAIT, or MNT_LAZY.
599 *
600 * When fsyncing data asynchronously just do one consolidated pass starting
601 * with the most negative block number. This may not get all the data due
602 * to dependancies.
603 *
604 * When fsyncing data synchronously do a data pass, then a metadata pass,
605 * then do additional data+metadata passes to try to get all the data out.
606 */
607 static int vfsync_wait_output(struct vnode *vp,
608 int (*waitoutput)(struct vnode *, struct thread *));
609 static int vfsync_dummy_cmp(struct buf *bp __unused, void *data __unused);
610 static int vfsync_data_only_cmp(struct buf *bp, void *data);
611 static int vfsync_meta_only_cmp(struct buf *bp, void *data);
612 static int vfsync_lazy_range_cmp(struct buf *bp, void *data);
613 static int vfsync_bp(struct buf *bp, void *data);
614
615 struct vfsync_info {
616 struct vnode *vp;
617 int synchronous;
618 int syncdeps;
619 int lazycount;
620 int lazylimit;
621 int skippedbufs;
622 int (*checkdef)(struct buf *);
623 int (*cmpfunc)(struct buf *, void *);
624 };
625
626 int
627 vfsync(struct vnode *vp, int waitfor, int passes,
628 int (*checkdef)(struct buf *),
629 int (*waitoutput)(struct vnode *, struct thread *))
630 {
631 struct vfsync_info info;
632 int error;
633
634 bzero(&info, sizeof(info));
635 info.vp = vp;
636 if ((info.checkdef = checkdef) == NULL)
637 info.syncdeps = 1;
638
639 lwkt_gettoken(&vp->v_token);
640
641 switch(waitfor) {
642 case MNT_LAZY | MNT_NOWAIT:
643 case MNT_LAZY:
644 /*
645 * Lazy (filesystem syncer typ) Asynchronous plus limit the
646 * number of data (not meta) pages we try to flush to 1MB.
647 * A non-zero return means that lazy limit was reached.
648 */
649 info.lazylimit = 1024 * 1024;
650 info.syncdeps = 1;
651 info.cmpfunc = vfsync_lazy_range_cmp;
652 error = RB_SCAN(buf_rb_tree, &vp->v_rbdirty_tree,
653 vfsync_lazy_range_cmp, vfsync_bp, &info);
654 info.cmpfunc = vfsync_meta_only_cmp;
655 RB_SCAN(buf_rb_tree, &vp->v_rbdirty_tree,
656 vfsync_meta_only_cmp, vfsync_bp, &info);
657 if (error == 0)
658 vp->v_lazyw = 0;
659 else if (!RB_EMPTY(&vp->v_rbdirty_tree))
660 vn_syncer_add(vp, 1);
661 error = 0;
662 break;
663 case MNT_NOWAIT:
664 /*
665 * Asynchronous. Do a data-only pass and a meta-only pass.
666 */
667 info.syncdeps = 1;
668 info.cmpfunc = vfsync_data_only_cmp;
669 RB_SCAN(buf_rb_tree, &vp->v_rbdirty_tree, vfsync_data_only_cmp,
670 vfsync_bp, &info);
671 info.cmpfunc = vfsync_meta_only_cmp;
672 RB_SCAN(buf_rb_tree, &vp->v_rbdirty_tree, vfsync_meta_only_cmp,
673 vfsync_bp, &info);
674 error = 0;
675 break;
676 default:
677 /*
678 * Synchronous. Do a data-only pass, then a meta-data+data
679 * pass, then additional integrated passes to try to get
680 * all the dependancies flushed.
681 */
682 info.cmpfunc = vfsync_data_only_cmp;
683 RB_SCAN(buf_rb_tree, &vp->v_rbdirty_tree, vfsync_data_only_cmp,
684 vfsync_bp, &info);
685 error = vfsync_wait_output(vp, waitoutput);
686 if (error == 0) {
687 info.skippedbufs = 0;
688 info.cmpfunc = vfsync_dummy_cmp;
689 RB_SCAN(buf_rb_tree, &vp->v_rbdirty_tree, NULL,
690 vfsync_bp, &info);
691 error = vfsync_wait_output(vp, waitoutput);
692 if (info.skippedbufs) {
693 kprintf("Warning: vfsync skipped %d dirty "
694 "bufs in pass2!\n", info.skippedbufs);
695 }
696 }
697 while (error == 0 && passes > 0 &&
698 !RB_EMPTY(&vp->v_rbdirty_tree)
699 ) {
700 if (--passes == 0) {
701 info.synchronous = 1;
702 info.syncdeps = 1;
703 }
704 info.cmpfunc = vfsync_dummy_cmp;
705 error = RB_SCAN(buf_rb_tree, &vp->v_rbdirty_tree, NULL,
706 vfsync_bp, &info);
707 if (error < 0)
708 error = -error;
709 info.syncdeps = 1;
710 if (error == 0)
711 error = vfsync_wait_output(vp, waitoutput);
712 }
713 break;
714 }
715 lwkt_reltoken(&vp->v_token);
716 return(error);
717 }
718
719 static int
720 vfsync_wait_output(struct vnode *vp,
721 int (*waitoutput)(struct vnode *, struct thread *))
722 {
723 int error;
724
725 error = bio_track_wait(&vp->v_track_write, 0, 0);
726 if (waitoutput)
727 error = waitoutput(vp, curthread);
728 return(error);
729 }
730
731 static int
732 vfsync_dummy_cmp(struct buf *bp __unused, void *data __unused)
733 {
734 return(0);
735 }
736
737 static int
738 vfsync_data_only_cmp(struct buf *bp, void *data)
739 {
740 if (bp->b_loffset < 0)
741 return(-1);
742 return(0);
743 }
744
745 static int
746 vfsync_meta_only_cmp(struct buf *bp, void *data)
747 {
748 if (bp->b_loffset < 0)
749 return(0);
750 return(1);
751 }
752
753 static int
754 vfsync_lazy_range_cmp(struct buf *bp, void *data)
755 {
756 struct vfsync_info *info = data;
757
758 if (bp->b_loffset < info->vp->v_lazyw)
759 return(-1);
760 return(0);
761 }
762
763 static int
764 vfsync_bp(struct buf *bp, void *data)
765 {
766 struct vfsync_info *info = data;
767 struct vnode *vp = info->vp;
768 int error;
769
770 /*
771 * Ignore buffers that we cannot immediately lock.
772 */
773 if (BUF_LOCK(bp, LK_EXCLUSIVE | LK_NOWAIT)) {
774 ++info->skippedbufs;
775 return(0);
776 }
777
778 /*
779 * We must revalidate the buffer after locking.
780 */
781 if ((bp->b_flags & B_DELWRI) == 0 ||
782 bp->b_vp != info->vp ||
783 info->cmpfunc(bp, data)) {
784 BUF_UNLOCK(bp);
785 return(0);
786 }
787
788 /*
789 * If syncdeps is not set we do not try to write buffers which have
790 * dependancies.
791 */
792 if (!info->synchronous && info->syncdeps == 0 && info->checkdef(bp)) {
793 BUF_UNLOCK(bp);
794 return(0);
795 }
796
797 /*
798 * B_NEEDCOMMIT (primarily used by NFS) is a state where the buffer
799 * has been written but an additional handshake with the device
800 * is required before we can dispose of the buffer. We have no idea
801 * how to do this so we have to skip these buffers.
802 */
803 if (bp->b_flags & B_NEEDCOMMIT) {
804 BUF_UNLOCK(bp);
805 return(0);
806 }
807
808 /*
809 * Ask bioops if it is ok to sync. If not the VFS may have
810 * set B_LOCKED so we have to cycle the buffer.
811 */
812 if (LIST_FIRST(&bp->b_dep) != NULL && buf_checkwrite(bp)) {
813 bremfree(bp);
814 brelse(bp);
815 return(0);
816 }
817
818 if (info->synchronous) {
819 /*
820 * Synchronous flushing. An error may be returned.
821 */
822 bremfree(bp);
823 error = bwrite(bp);
824 } else {
825 /*
826 * Asynchronous flushing. A negative return value simply
827 * stops the scan and is not considered an error. We use
828 * this to support limited MNT_LAZY flushes.
829 */
830 vp->v_lazyw = bp->b_loffset;
831 bremfree(bp);
832 info->lazycount += cluster_awrite(bp);
833 waitrunningbufspace();
834 vm_wait_nominal();
835 if (info->lazylimit && info->lazycount >= info->lazylimit)
836 error = 1;
837 else
838 error = 0;
839 }
840 return(-error);
841 }
842
843 /*
844 * Associate a buffer with a vnode.
845 *
846 * MPSAFE
847 */
848 int
849 bgetvp(struct vnode *vp, struct buf *bp, int testsize)
850 {
851 KASSERT(bp->b_vp == NULL, ("bgetvp: not free"));
852 KKASSERT((bp->b_flags & (B_HASHED|B_DELWRI|B_VNCLEAN|B_VNDIRTY)) == 0);
853
854 /*
855 * Insert onto list for new vnode.
856 */
857 lwkt_gettoken(&vp->v_token);
858
859 if (buf_rb_hash_RB_INSERT(&vp->v_rbhash_tree, bp)) {
860 lwkt_reltoken(&vp->v_token);
861 return (EEXIST);
862 }
863
864 /*
865 * Diagnostics (mainly for HAMMER debugging). Check for
866 * overlapping buffers.
867 */
868 if (check_buf_overlap) {
869 struct buf *bx;
870 bx = buf_rb_hash_RB_PREV(bp);
871 if (bx) {
872 if (bx->b_loffset + bx->b_bufsize > bp->b_loffset) {
873 kprintf("bgetvp: overlapl %016jx/%d %016jx "
874 "bx %p bp %p\n",
875 (intmax_t)bx->b_loffset,
876 bx->b_bufsize,
877 (intmax_t)bp->b_loffset,
878 bx, bp);
879 if (check_buf_overlap > 1)
880 panic("bgetvp - overlapping buffer");
881 }
882 }
883 bx = buf_rb_hash_RB_NEXT(bp);
884 if (bx) {
885 if (bp->b_loffset + testsize > bx->b_loffset) {
886 kprintf("bgetvp: overlapr %016jx/%d %016jx "
887 "bp %p bx %p\n",
888 (intmax_t)bp->b_loffset,
889 testsize,
890 (intmax_t)bx->b_loffset,
891 bp, bx);
892 if (check_buf_overlap > 1)
893 panic("bgetvp - overlapping buffer");
894 }
895 }
896 }
897 bp->b_vp = vp;
898 bp->b_flags |= B_HASHED;
899 bp->b_flags |= B_VNCLEAN;
900 if (buf_rb_tree_RB_INSERT(&vp->v_rbclean_tree, bp))
901 panic("reassignbuf: dup lblk/clean vp %p bp %p", vp, bp);
902 /*vhold(vp);*/
903 lwkt_reltoken(&vp->v_token);
904 return(0);
905 }
906
907 /*
908 * Disassociate a buffer from a vnode.
909 *
910 * MPSAFE
911 */
912 void
913 brelvp(struct buf *bp)
914 {
915 struct vnode *vp;
916
917 KASSERT(bp->b_vp != NULL, ("brelvp: NULL"));
918
919 /*
920 * Delete from old vnode list, if on one.
921 */
922 vp = bp->b_vp;
923 lwkt_gettoken(&vp->v_token);
924 if (bp->b_flags & (B_VNDIRTY | B_VNCLEAN)) {
925 if (bp->b_flags & B_VNDIRTY)
926 buf_rb_tree_RB_REMOVE(&vp->v_rbdirty_tree, bp);
927 else
928 buf_rb_tree_RB_REMOVE(&vp->v_rbclean_tree, bp);
929 bp->b_flags &= ~(B_VNDIRTY | B_VNCLEAN);
930 }
931 if (bp->b_flags & B_HASHED) {
932 buf_rb_hash_RB_REMOVE(&vp->v_rbhash_tree, bp);
933 bp->b_flags &= ~B_HASHED;
934 }
935
936 /*
937 * Only remove from synclist when no dirty buffers are left AND
938 * the VFS has not flagged the vnode's inode as being dirty.
939 */
940 if ((vp->v_flag & (VONWORKLST | VISDIRTY | VOBJDIRTY)) == VONWORKLST &&
941 RB_EMPTY(&vp->v_rbdirty_tree)) {
942 vn_syncer_remove(vp);
943 }
944 bp->b_vp = NULL;
945
946 lwkt_reltoken(&vp->v_token);
947
948 /*vdrop(vp);*/
949 }
950
951 /*
952 * Reassign the buffer to the proper clean/dirty list based on B_DELWRI.
953 * This routine is called when the state of the B_DELWRI bit is changed.
954 *
955 * Must be called with vp->v_token held.
956 * MPSAFE
957 */
958 void
959 reassignbuf(struct buf *bp)
960 {
961 struct vnode *vp = bp->b_vp;
962 int delay;
963
964 ASSERT_LWKT_TOKEN_HELD(&vp->v_token);
965 ++reassignbufcalls;
966
967 /*
968 * B_PAGING flagged buffers cannot be reassigned because their vp
969 * is not fully linked in.
970 */
971 if (bp->b_flags & B_PAGING)
972 panic("cannot reassign paging buffer");
973
974 if (bp->b_flags & B_DELWRI) {
975 /*
976 * Move to the dirty list, add the vnode to the worklist
977 */
978 if (bp->b_flags & B_VNCLEAN) {
979 buf_rb_tree_RB_REMOVE(&vp->v_rbclean_tree, bp);
980 bp->b_flags &= ~B_VNCLEAN;
981 }
982 if ((bp->b_flags & B_VNDIRTY) == 0) {
983 if (buf_rb_tree_RB_INSERT(&vp->v_rbdirty_tree, bp)) {
984 panic("reassignbuf: dup lblk vp %p bp %p",
985 vp, bp);
986 }
987 bp->b_flags |= B_VNDIRTY;
988 }
989 if ((vp->v_flag & VONWORKLST) == 0) {
990 switch (vp->v_type) {
991 case VDIR:
992 delay = dirdelay;
993 break;
994 case VCHR:
995 case VBLK:
996 if (vp->v_rdev &&
997 vp->v_rdev->si_mountpoint != NULL) {
998 delay = metadelay;
999 break;
1000 }
1001 /* fall through */
1002 default:
1003 delay = filedelay;
1004 }
1005 vn_syncer_add(vp, delay);
1006 }
1007 } else {
1008 /*
1009 * Move to the clean list, remove the vnode from the worklist
1010 * if no dirty blocks remain.
1011 */
1012 if (bp->b_flags & B_VNDIRTY) {
1013 buf_rb_tree_RB_REMOVE(&vp->v_rbdirty_tree, bp);
1014 bp->b_flags &= ~B_VNDIRTY;
1015 }
1016 if ((bp->b_flags & B_VNCLEAN) == 0) {
1017 if (buf_rb_tree_RB_INSERT(&vp->v_rbclean_tree, bp)) {
1018 panic("reassignbuf: dup lblk vp %p bp %p",
1019 vp, bp);
1020 }
1021 bp->b_flags |= B_VNCLEAN;
1022 }
1023
1024 /*
1025 * Only remove from synclist when no dirty buffers are left
1026 * AND the VFS has not flagged the vnode's inode as being
1027 * dirty.
1028 */
1029 if ((vp->v_flag & (VONWORKLST | VISDIRTY | VOBJDIRTY)) ==
1030 VONWORKLST &&
1031 RB_EMPTY(&vp->v_rbdirty_tree)) {
1032 vn_syncer_remove(vp);
1033 }
1034 }
1035 }
1036
1037 /*
1038 * Create a vnode for a block device. Used for mounting the root file
1039 * system.
1040 *
1041 * A vref()'d vnode is returned.
1042 */
1043 extern struct vop_ops *devfs_vnode_dev_vops_p;
1044 int
1045 bdevvp(cdev_t dev, struct vnode **vpp)
1046 {
1047 struct vnode *vp;
1048 struct vnode *nvp;
1049 int error;
1050
1051 if (dev == NULL) {
1052 *vpp = NULLVP;
1053 return (ENXIO);
1054 }
1055 error = getspecialvnode(VT_NON, NULL, &devfs_vnode_dev_vops_p,
1056 &nvp, 0, 0);
1057 if (error) {
1058 *vpp = NULLVP;
1059 return (error);
1060 }
1061 vp = nvp;
1062 vp->v_type = VCHR;
1063 #if 0
1064 vp->v_rdev = dev;
1065 #endif
1066 v_associate_rdev(vp, dev);
1067 vp->v_umajor = dev->si_umajor;
1068 vp->v_uminor = dev->si_uminor;
1069 vx_unlock(vp);
1070 *vpp = vp;
1071 return (0);
1072 }
1073
1074 int
1075 v_associate_rdev(struct vnode *vp, cdev_t dev)
1076 {
1077 if (dev == NULL)
1078 return(ENXIO);
1079 if (dev_is_good(dev) == 0)
1080 return(ENXIO);
1081 KKASSERT(vp->v_rdev == NULL);
1082 vp->v_rdev = reference_dev(dev);
1083 lwkt_gettoken(&spechash_token);
1084 SLIST_INSERT_HEAD(&dev->si_hlist, vp, v_cdevnext);
1085 lwkt_reltoken(&spechash_token);
1086 return(0);
1087 }
1088
1089 void
1090 v_release_rdev(struct vnode *vp)
1091 {
1092 cdev_t dev;
1093
1094 if ((dev = vp->v_rdev) != NULL) {
1095 lwkt_gettoken(&spechash_token);
1096 SLIST_REMOVE(&dev->si_hlist, vp, vnode, v_cdevnext);
1097 vp->v_rdev = NULL;
1098 release_dev(dev);
1099 lwkt_reltoken(&spechash_token);
1100 }
1101 }
1102
1103 /*
1104 * Add a vnode to the alias list hung off the cdev_t. We only associate
1105 * the device number with the vnode. The actual device is not associated
1106 * until the vnode is opened (usually in spec_open()), and will be
1107 * disassociated on last close.
1108 */
1109 void
1110 addaliasu(struct vnode *nvp, int x, int y)
1111 {
1112 if (nvp->v_type != VBLK && nvp->v_type != VCHR)
1113 panic("addaliasu on non-special vnode");
1114 nvp->v_umajor = x;
1115 nvp->v_uminor = y;
1116 }
1117
1118 /*
1119 * Simple call that a filesystem can make to try to get rid of a
1120 * vnode. It will fail if anyone is referencing the vnode (including
1121 * the caller).
1122 *
1123 * The filesystem can check whether its in-memory inode structure still
1124 * references the vp on return.
1125 *
1126 * May only be called if the vnode is in a known state (i.e. being prevented
1127 * from being deallocated by some other condition such as a vfs inode hold).
1128 */
1129 void
1130 vclean_unlocked(struct vnode *vp)
1131 {
1132 vx_get(vp);
1133 if (VREFCNT(vp) <= 0)
1134 vgone_vxlocked(vp);
1135 vx_put(vp);
1136 }
1137
1138 /*
1139 * Disassociate a vnode from its underlying filesystem.
1140 *
1141 * The vnode must be VX locked and referenced. In all normal situations
1142 * there are no active references. If vclean_vxlocked() is called while
1143 * there are active references, the vnode is being ripped out and we have
1144 * to call VOP_CLOSE() as appropriate before we can reclaim it.
1145 */
1146 void
1147 vclean_vxlocked(struct vnode *vp, int flags)
1148 {
1149 int active;
1150 int n;
1151 vm_object_t object;
1152 struct namecache *ncp;
1153
1154 /*
1155 * If the vnode has already been reclaimed we have nothing to do.
1156 */
1157 if (vp->v_flag & VRECLAIMED)
1158 return;
1159
1160 /*
1161 * Set flag to interlock operation, flag finalization to ensure
1162 * that the vnode winds up on the inactive list, and set v_act to 0.
1163 */
1164 vsetflags(vp, VRECLAIMED);
1165 atomic_set_int(&vp->v_refcnt, VREF_FINALIZE);
1166 vp->v_act = 0;
1167
1168 if (verbose_reclaims) {
1169 if ((ncp = TAILQ_FIRST(&vp->v_namecache)) != NULL)
1170 kprintf("Debug: reclaim %p %s\n", vp, ncp->nc_name);
1171 }
1172
1173 /*
1174 * Scrap the vfs cache
1175 */
1176 while (cache_inval_vp(vp, 0) != 0) {
1177 kprintf("Warning: vnode %p clean/cache_resolution "
1178 "race detected\n", vp);
1179 tsleep(vp, 0, "vclninv", 2);
1180 }
1181
1182 /*
1183 * Check to see if the vnode is in use. If so we have to reference it
1184 * before we clean it out so that its count cannot fall to zero and
1185 * generate a race against ourselves to recycle it.
1186 */
1187 active = (VREFCNT(vp) > 0);
1188
1189 /*
1190 * Clean out any buffers associated with the vnode and destroy its
1191 * object, if it has one.
1192 */
1193 vinvalbuf(vp, V_SAVE, 0, 0);
1194 KKASSERT(lockcountnb(&vp->v_lock) == 1);
1195
1196 /*
1197 * If purging an active vnode (typically during a forced unmount
1198 * or reboot), it must be closed and deactivated before being
1199 * reclaimed. This isn't really all that safe, but what can
1200 * we do? XXX.
1201 *
1202 * Note that neither of these routines unlocks the vnode.
1203 */
1204 if (active && (flags & DOCLOSE)) {
1205 while ((n = vp->v_opencount) != 0) {
1206 if (vp->v_writecount)
1207 VOP_CLOSE(vp, FWRITE|FNONBLOCK);
1208 else
1209 VOP_CLOSE(vp, FNONBLOCK);
1210 if (vp->v_opencount == n) {
1211 kprintf("Warning: unable to force-close"
1212 " vnode %p\n", vp);
1213 break;
1214 }
1215 }
1216 }
1217
1218 /*
1219 * If the vnode has not been deactivated, deactivated it. Deactivation
1220 * can create new buffers and VM pages so we have to call vinvalbuf()
1221 * again to make sure they all get flushed.
1222 *
1223 * This can occur if a file with a link count of 0 needs to be
1224 * truncated.
1225 *
1226 * If the vnode is already dead don't try to deactivate it.
1227 */
1228 if ((vp->v_flag & VINACTIVE) == 0) {
1229 vsetflags(vp, VINACTIVE);
1230 if (vp->v_mount)
1231 VOP_INACTIVE(vp);
1232 vinvalbuf(vp, V_SAVE, 0, 0);
1233 }
1234 KKASSERT(lockcountnb(&vp->v_lock) == 1);
1235
1236 /*
1237 * If the vnode has an object, destroy it.
1238 */
1239 while ((object = vp->v_object) != NULL) {
1240 vm_object_hold(object);
1241 if (object == vp->v_object)
1242 break;
1243 vm_object_drop(object);
1244 }
1245
1246 if (object != NULL) {
1247 if (object->ref_count == 0) {
1248 if ((object->flags & OBJ_DEAD) == 0)
1249 vm_object_terminate(object);
1250 vm_object_drop(object);
1251 vclrflags(vp, VOBJBUF);
1252 } else {
1253 vm_pager_deallocate(object);
1254 vclrflags(vp, VOBJBUF);
1255 vm_object_drop(object);
1256 }
1257 }
1258 KKASSERT((vp->v_flag & VOBJBUF) == 0);
1259
1260 /*
1261 * Reclaim the vnode if not already dead.
1262 */
1263 if (vp->v_mount && VOP_RECLAIM(vp))
1264 panic("vclean: cannot reclaim");
1265
1266 /*
1267 * Done with purge, notify sleepers of the grim news.
1268 */
1269 vp->v_ops = &dead_vnode_vops_p;
1270 vn_gone(vp);
1271 vp->v_tag = VT_NON;
1272
1273 /*
1274 * If we are destroying an active vnode, reactivate it now that
1275 * we have reassociated it with deadfs. This prevents the system
1276 * from crashing on the vnode due to it being unexpectedly marked
1277 * as inactive or reclaimed.
1278 */
1279 if (active && (flags & DOCLOSE)) {
1280 vclrflags(vp, VINACTIVE | VRECLAIMED);
1281 }
1282 }
1283
1284 /*
1285 * Eliminate all activity associated with the requested vnode
1286 * and with all vnodes aliased to the requested vnode.
1287 *
1288 * The vnode must be referenced but should not be locked.
1289 */
1290 int
1291 vrevoke(struct vnode *vp, struct ucred *cred)
1292 {
1293 struct vnode *vq;
1294 struct vnode *vqn;
1295 cdev_t dev;
1296 int error;
1297
1298 /*
1299 * If the vnode has a device association, scrap all vnodes associated
1300 * with the device. Don't let the device disappear on us while we
1301 * are scrapping the vnodes.
1302 *
1303 * The passed vp will probably show up in the list, do not VX lock
1304 * it twice!
1305 *
1306 * Releasing the vnode's rdev here can mess up specfs's call to
1307 * device close, so don't do it. The vnode has been disassociated
1308 * and the device will be closed after the last ref on the related
1309 * fp goes away (if not still open by e.g. the kernel).
1310 */
1311 if (vp->v_type != VCHR) {
1312 error = fdrevoke(vp, DTYPE_VNODE, cred);
1313 return (error);
1314 }
1315 if ((dev = vp->v_rdev) == NULL) {
1316 return(0);
1317 }
1318 reference_dev(dev);
1319 lwkt_gettoken(&spechash_token);
1320
1321 restart:
1322 vqn = SLIST_FIRST(&dev->si_hlist);
1323 if (vqn)
1324 vhold(vqn);
1325 while ((vq = vqn) != NULL) {
1326 if (VREFCNT(vq) > 0) {
1327 vref(vq);
1328 fdrevoke(vq, DTYPE_VNODE, cred);
1329 /*v_release_rdev(vq);*/
1330 vrele(vq);
1331 if (vq->v_rdev != dev) {
1332 vdrop(vq);
1333 goto restart;
1334 }
1335 }
1336 vqn = SLIST_NEXT(vq, v_cdevnext);
1337 if (vqn)
1338 vhold(vqn);
1339 vdrop(vq);
1340 }
1341 lwkt_reltoken(&spechash_token);
1342 dev_drevoke(dev);
1343 release_dev(dev);
1344 return (0);
1345 }
1346
1347 /*
1348 * This is called when the object underlying a vnode is being destroyed,
1349 * such as in a remove(). Try to recycle the vnode immediately if the
1350 * only active reference is our reference.
1351 *
1352 * Directory vnodes in the namecache with children cannot be immediately
1353 * recycled because numerous VOP_N*() ops require them to be stable.
1354 *
1355 * To avoid recursive recycling from VOP_INACTIVE implemenetations this
1356 * function is a NOP if VRECLAIMED is already set.
1357 */
1358 int
1359 vrecycle(struct vnode *vp)
1360 {
1361 if (VREFCNT(vp) <= 1 && (vp->v_flag & VRECLAIMED) == 0) {
1362 if (cache_inval_vp_nonblock(vp))
1363 return(0);
1364 vgone_vxlocked(vp);
1365 return (1);
1366 }
1367 return (0);
1368 }
1369
1370 /*
1371 * Return the maximum I/O size allowed for strategy calls on VP.
1372 *
1373 * If vp is VCHR or VBLK we dive the device, otherwise we use
1374 * the vp's mount info.
1375 *
1376 * The returned value is clamped at MAXPHYS as most callers cannot use
1377 * buffers larger than that size.
1378 */
1379 int
1380 vmaxiosize(struct vnode *vp)
1381 {
1382 int maxiosize;
1383
1384 if (vp->v_type == VBLK || vp->v_type == VCHR)
1385 maxiosize = vp->v_rdev->si_iosize_max;
1386 else
1387 maxiosize = vp->v_mount->mnt_iosize_max;
1388
1389 if (maxiosize > MAXPHYS)
1390 maxiosize = MAXPHYS;
1391 return (maxiosize);
1392 }
1393
1394 /*
1395 * Eliminate all activity associated with a vnode in preparation for
1396 * destruction.
1397 *
1398 * The vnode must be VX locked and refd and will remain VX locked and refd
1399 * on return. This routine may be called with the vnode in any state, as
1400 * long as it is VX locked. The vnode will be cleaned out and marked
1401 * VRECLAIMED but will not actually be reused until all existing refs and
1402 * holds go away.
1403 *
1404 * NOTE: This routine may be called on a vnode which has not yet been
1405 * already been deactivated (VOP_INACTIVE), or on a vnode which has
1406 * already been reclaimed.
1407 *
1408 * This routine is not responsible for placing us back on the freelist.
1409 * Instead, it happens automatically when the caller releases the VX lock
1410 * (assuming there aren't any other references).
1411 */
1412 void
1413 vgone_vxlocked(struct vnode *vp)
1414 {
1415 /*
1416 * assert that the VX lock is held. This is an absolute requirement
1417 * now for vgone_vxlocked() to be called.
1418 */
1419 KKASSERT(lockcountnb(&vp->v_lock) == 1);
1420
1421 /*
1422 * Clean out the filesystem specific data and set the VRECLAIMED
1423 * bit. Also deactivate the vnode if necessary.
1424 *
1425 * The vnode should have automatically been removed from the syncer
1426 * list as syncer/dirty flags cleared during the cleaning.
1427 */
1428 vclean_vxlocked(vp, DOCLOSE);
1429 KKASSERT((vp->v_flag & VONWORKLST) == 0);
1430
1431 /*
1432 * Delete from old mount point vnode list, if on one.
1433 */
1434 if (vp->v_mount != NULL) {
1435 KKASSERT(vp->v_data == NULL);
1436 insmntque(vp, NULL);
1437 }
1438
1439 /*
1440 * If special device, remove it from special device alias list
1441 * if it is on one. This should normally only occur if a vnode is
1442 * being revoked as the device should otherwise have been released
1443 * naturally.
1444 */
1445 if ((vp->v_type == VBLK || vp->v_type == VCHR) && vp->v_rdev != NULL) {
1446 v_release_rdev(vp);
1447 }
1448
1449 /*
1450 * Set us to VBAD
1451 */
1452 vp->v_type = VBAD;
1453 }
1454
1455 /*
1456 * Lookup a vnode by device number.
1457 *
1458 * Returns non-zero and *vpp set to a vref'd vnode on success.
1459 * Returns zero on failure.
1460 */
1461 int
1462 vfinddev(cdev_t dev, enum vtype type, struct vnode **vpp)
1463 {
1464 struct vnode *vp;
1465
1466 lwkt_gettoken(&spechash_token);
1467 SLIST_FOREACH(vp, &dev->si_hlist, v_cdevnext) {
1468 if (type == vp->v_type) {
1469 *vpp = vp;
1470 vref(vp);
1471 lwkt_reltoken(&spechash_token);
1472 return (1);
1473 }
1474 }
1475 lwkt_reltoken(&spechash_token);
1476 return (0);
1477 }
1478
1479 /*
1480 * Calculate the total number of references to a special device. This
1481 * routine may only be called for VBLK and VCHR vnodes since v_rdev is
1482 * an overloaded field. Since udev2dev can now return NULL, we have
1483 * to check for a NULL v_rdev.
1484 */
1485 int
1486 count_dev(cdev_t dev)
1487 {
1488 struct vnode *vp;
1489 int count = 0;
1490
1491 if (SLIST_FIRST(&dev->si_hlist)) {
1492 lwkt_gettoken(&spechash_token);
1493 SLIST_FOREACH(vp, &dev->si_hlist, v_cdevnext) {
1494 count += vp->v_opencount;
1495 }
1496 lwkt_reltoken(&spechash_token);
1497 }
1498 return(count);
1499 }
1500
1501 int
1502 vcount(struct vnode *vp)
1503 {
1504 if (vp->v_rdev == NULL)
1505 return(0);
1506 return(count_dev(vp->v_rdev));
1507 }
1508
1509 /*
1510 * Initialize VMIO for a vnode. This routine MUST be called before a
1511 * VFS can issue buffer cache ops on a vnode. It is typically called
1512 * when a vnode is initialized from its inode.
1513 */
1514 int
1515 vinitvmio(struct vnode *vp, off_t filesize, int blksize, int boff)
1516 {
1517 vm_object_t object;
1518 int error = 0;
1519
1520 object = vp->v_object;
1521 if (object) {
1522 vm_object_hold(object);
1523 KKASSERT(vp->v_object == object);
1524 }
1525
1526 if (object == NULL) {
1527 object = vnode_pager_alloc(vp, filesize, 0, 0, blksize, boff);
1528
1529 /*
1530 * Dereference the reference we just created. This assumes
1531 * that the object is associated with the vp. Allow it to
1532 * have zero refs. It cannot be destroyed as long as it
1533 * is associated with the vnode.
1534 */
1535 vm_object_hold(object);
1536 atomic_add_int(&object->ref_count, -1);
1537 vrele(vp);
1538 } else {
1539 KKASSERT((object->flags & OBJ_DEAD) == 0);
1540 }
1541 KASSERT(vp->v_object != NULL, ("vinitvmio: NULL object"));
1542 vsetflags(vp, VOBJBUF);
1543 vm_object_drop(object);
1544
1545 return (error);
1546 }
1547
1548
1549 /*
1550 * Print out a description of a vnode.
1551 */
1552 static char *typename[] =
1553 {"VNON", "VREG", "VDIR", "VBLK", "VCHR", "VLNK", "VSOCK", "VFIFO", "VBAD"};
1554
1555 void
1556 vprint(char *label, struct vnode *vp)
1557 {
1558 char buf[96];
1559
1560 if (label != NULL)
1561 kprintf("%s: %p: ", label, (void *)vp);
1562 else
1563 kprintf("%p: ", (void *)vp);
1564 kprintf("type %s, refcnt %08x, writecount %d, holdcnt %d,",
1565 typename[vp->v_type],
1566 vp->v_refcnt, vp->v_writecount, vp->v_auxrefs);
1567 buf[0] = '\0';
1568 if (vp->v_flag & VROOT)
1569 strcat(buf, "|VROOT");
1570 if (vp->v_flag & VPFSROOT)
1571 strcat(buf, "|VPFSROOT");
1572 if (vp->v_flag & VTEXT)
1573 strcat(buf, "|VTEXT");
1574 if (vp->v_flag & VSYSTEM)
1575 strcat(buf, "|VSYSTEM");
1576 if (vp->v_flag & VOBJBUF)
1577 strcat(buf, "|VOBJBUF");
1578 if (buf[0] != '\0')
1579 kprintf(" flags (%s)", &buf[1]);
1580 if (vp->v_data == NULL) {
1581 kprintf("\n");
1582 } else {
1583 kprintf("\n\t");
1584 VOP_PRINT(vp);
1585 }
1586 }
1587
1588 /*
1589 * Do the usual access checking.
1590 * file_mode, uid and gid are from the vnode in question,
1591 * while acc_mode and cred are from the VOP_ACCESS parameter list
1592 */
1593 int
1594 vaccess(enum vtype type, mode_t file_mode, uid_t uid, gid_t gid,
1595 mode_t acc_mode, struct ucred *cred)
1596 {
1597 mode_t mask;
1598 int ismember;
1599
1600 /*
1601 * Super-user always gets read/write access, but execute access depends
1602 * on at least one execute bit being set.
1603 */
1604 if (priv_check_cred(cred, PRIV_ROOT, 0) == 0) {
1605 if ((acc_mode & VEXEC) && type != VDIR &&
1606 (file_mode & (S_IXUSR|S_IXGRP|S_IXOTH)) == 0)
1607 return (EACCES);
1608 return (0);
1609 }
1610
1611 mask = 0;
1612
1613 /* Otherwise, check the owner. */
1614 if (cred->cr_uid == uid) {
1615 if (acc_mode & VEXEC)
1616 mask |= S_IXUSR;
1617 if (acc_mode & VREAD)
1618 mask |= S_IRUSR;
1619 if (acc_mode & VWRITE)
1620 mask |= S_IWUSR;
1621 return ((file_mode & mask) == mask ? 0 : EACCES);
1622 }
1623
1624 /* Otherwise, check the groups. */
1625 ismember = groupmember(gid, cred);
1626 if (cred->cr_svgid == gid || ismember) {
1627 if (acc_mode & VEXEC)
1628 mask |= S_IXGRP;
1629 if (acc_mode & VREAD)
1630 mask |= S_IRGRP;
1631 if (acc_mode & VWRITE)
1632 mask |= S_IWGRP;
1633 return ((file_mode & mask) == mask ? 0 : EACCES);
1634 }
1635
1636 /* Otherwise, check everyone else. */
1637 if (acc_mode & VEXEC)
1638 mask |= S_IXOTH;
1639 if (acc_mode & VREAD)
1640 mask |= S_IROTH;
1641 if (acc_mode & VWRITE)
1642 mask |= S_IWOTH;
1643 return ((file_mode & mask) == mask ? 0 : EACCES);
1644 }
1645
1646 #ifdef DDB
1647 #include <ddb/ddb.h>
1648
1649 static int db_show_locked_vnodes(struct mount *mp, void *data);
1650
1651 /*
1652 * List all of the locked vnodes in the system.
1653 * Called when debugging the kernel.
1654 */
1655 DB_SHOW_COMMAND(lockedvnodes, lockedvnodes)
1656 {
1657 kprintf("Locked vnodes\n");
1658 mountlist_scan(db_show_locked_vnodes, NULL,
1659 MNTSCAN_FORWARD|MNTSCAN_NOBUSY);
1660 }
1661
1662 static int
1663 db_show_locked_vnodes(struct mount *mp, void *data __unused)
1664 {
1665 struct vnode *vp;
1666
1667 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) {
1668 if (vn_islocked(vp))
1669 vprint(NULL, vp);
1670 }
1671 return(0);
1672 }
1673 #endif
1674
1675 /*
1676 * Top level filesystem related information gathering.
1677 */
1678 static int sysctl_ovfs_conf (SYSCTL_HANDLER_ARGS);
1679
1680 static int
1681 vfs_sysctl(SYSCTL_HANDLER_ARGS)
1682 {
1683 int *name = (int *)arg1 - 1; /* XXX */
1684 u_int namelen = arg2 + 1; /* XXX */
1685 struct vfsconf *vfsp;
1686 int maxtypenum;
1687
1688 #if 1 || defined(COMPAT_PRELITE2)
1689 /* Resolve ambiguity between VFS_VFSCONF and VFS_GENERIC. */
1690 if (namelen == 1)
1691 return (sysctl_ovfs_conf(oidp, arg1, arg2, req));
1692 #endif
1693
1694 #ifdef notyet
1695 /* all sysctl names at this level are at least name and field */
1696 if (namelen < 2)
1697 return (ENOTDIR); /* overloaded */
1698 if (name[0] != VFS_GENERIC) {
1699 vfsp = vfsconf_find_by_typenum(name[0]);
1700 if (vfsp == NULL)
1701 return (EOPNOTSUPP);
1702 return ((*vfsp->vfc_vfsops->vfs_sysctl)(&name[1], namelen - 1,
1703 oldp, oldlenp, newp, newlen, p));
1704 }
1705 #endif
1706 switch (name[1]) {
1707 case VFS_MAXTYPENUM:
1708 if (namelen != 2)
1709 return (ENOTDIR);
1710 maxtypenum = vfsconf_get_maxtypenum();
1711 return (SYSCTL_OUT(req, &maxtypenum, sizeof(maxtypenum)));
1712 case VFS_CONF:
1713 if (namelen != 3)
1714 return (ENOTDIR); /* overloaded */
1715 vfsp = vfsconf_find_by_typenum(name[2]);
1716 if (vfsp == NULL)
1717 return (EOPNOTSUPP);
1718 return (SYSCTL_OUT(req, vfsp, sizeof *vfsp));
1719 }
1720 return (EOPNOTSUPP);
1721 }
1722
1723 SYSCTL_NODE(_vfs, VFS_GENERIC, generic, CTLFLAG_RD, vfs_sysctl,
1724 "Generic filesystem");
1725
1726 #if 1 || defined(COMPAT_PRELITE2)
1727
1728 static int
1729 sysctl_ovfs_conf_iter(struct vfsconf *vfsp, void *data)
1730 {
1731 int error;
1732 struct ovfsconf ovfs;
1733 struct sysctl_req *req = (struct sysctl_req*) data;
1734
1735 bzero(&ovfs, sizeof(ovfs));
1736 ovfs.vfc_vfsops = vfsp->vfc_vfsops; /* XXX used as flag */
1737 strcpy(ovfs.vfc_name, vfsp->vfc_name);
1738 ovfs.vfc_index = vfsp->vfc_typenum;
1739 ovfs.vfc_refcount = vfsp->vfc_refcount;
1740 ovfs.vfc_flags = vfsp->vfc_flags;
1741 error = SYSCTL_OUT(req, &ovfs, sizeof ovfs);
1742 if (error)
1743 return error; /* abort iteration with error code */
1744 else
1745 return 0; /* continue iterating with next element */
1746 }
1747
1748 static int
1749 sysctl_ovfs_conf(SYSCTL_HANDLER_ARGS)
1750 {
1751 return vfsconf_each(sysctl_ovfs_conf_iter, (void*)req);
1752 }
1753
1754 #endif /* 1 || COMPAT_PRELITE2 */
1755
1756 /*
1757 * Check to see if a filesystem is mounted on a block device.
1758 */
1759 int
1760 vfs_mountedon(struct vnode *vp)
1761 {
1762 cdev_t dev;
1763
1764 if ((dev = vp->v_rdev) == NULL) {
1765 /* if (vp->v_type != VBLK)
1766 dev = get_dev(vp->v_uminor, vp->v_umajor); */
1767 }
1768 if (dev != NULL && dev->si_mountpoint)
1769 return (EBUSY);
1770 return (0);
1771 }
1772
1773 /*
1774 * Unmount all filesystems. The list is traversed in reverse order
1775 * of mounting to avoid dependencies.
1776 */
1777
1778 static int vfs_umountall_callback(struct mount *mp, void *data);
1779
1780 void
1781 vfs_unmountall(void)
1782 {
1783 int count;
1784
1785 do {
1786 count = mountlist_scan(vfs_umountall_callback,
1787 NULL, MNTSCAN_REVERSE|MNTSCAN_NOBUSY);
1788 } while (count);
1789 }
1790
1791 static
1792 int
1793 vfs_umountall_callback(struct mount *mp, void *data)
1794 {
1795 int error;
1796
1797 error = dounmount(mp, MNT_FORCE);
1798 if (error) {
1799 mountlist_remove(mp);
1800 kprintf("unmount of filesystem mounted from %s failed (",
1801 mp->mnt_stat.f_mntfromname);
1802 if (error == EBUSY)
1803 kprintf("BUSY)\n");
1804 else
1805 kprintf("%d)\n", error);
1806 }
1807 return(1);
1808 }
1809
1810 /*
1811 * Checks the mount flags for parameter mp and put the names comma-separated
1812 * into a string buffer buf with a size limit specified by len.
1813 *
1814 * It returns the number of bytes written into buf, and (*errorp) will be
1815 * set to 0, EINVAL (if passed length is 0), or ENOSPC (supplied buffer was
1816 * not large enough). The buffer will be 0-terminated if len was not 0.
1817 */
1818 size_t
1819 vfs_flagstostr(int flags, const struct mountctl_opt *optp,
1820 char *buf, size_t len, int *errorp)
1821 {
1822 static const struct mountctl_opt optnames[] = {
1823 { MNT_ASYNC, "asynchronous" },
1824 { MNT_EXPORTED, "NFS exported" },
1825 { MNT_LOCAL, "local" },
1826 { MNT_NOATIME, "noatime" },
1827 { MNT_NODEV, "nodev" },
1828 { MNT_NOEXEC, "noexec" },
1829 { MNT_NOSUID, "nosuid" },
1830 { MNT_NOSYMFOLLOW, "nosymfollow" },
1831 { MNT_QUOTA, "with-quotas" },
1832 { MNT_RDONLY, "read-only" },
1833 { MNT_SYNCHRONOUS, "synchronous" },
1834 { MNT_UNION, "union" },
1835 { MNT_NOCLUSTERR, "noclusterr" },
1836 { MNT_NOCLUSTERW, "noclusterw" },
1837 { MNT_SUIDDIR, "suiddir" },
1838 { MNT_SOFTDEP, "soft-updates" },
1839 { MNT_IGNORE, "ignore" },
1840 { 0, NULL}
1841 };
1842 int bwritten;
1843 int bleft;
1844 int optlen;
1845 int actsize;
1846
1847 *errorp = 0;
1848 bwritten = 0;
1849 bleft = len - 1; /* leave room for trailing \0 */
1850
1851 /*
1852 * Checks the size of the string. If it contains
1853 * any data, then we will append the new flags to
1854 * it.
1855 */
1856 actsize = strlen(buf);
1857 if (actsize > 0)
1858 buf += actsize;
1859
1860 /* Default flags if no flags passed */
1861 if (optp == NULL)
1862 optp = optnames;
1863
1864 if (bleft < 0) { /* degenerate case, 0-length buffer */
1865 *errorp = EINVAL;
1866 return(0);
1867 }
1868
1869 for (; flags && optp->o_opt; ++optp) {
1870 if ((flags & optp->o_opt) == 0)
1871 continue;
1872 optlen = strlen(optp->o_name);
1873 if (bwritten || actsize > 0) {
1874 if (bleft < 2) {
1875 *errorp = ENOSPC;
1876 break;
1877 }
1878 buf[bwritten++] = ',';
1879 buf[bwritten++] = ' ';
1880 bleft -= 2;
1881 }
1882 if (bleft < optlen) {
1883 *errorp = ENOSPC;
1884 break;
1885 }
1886 bcopy(optp->o_name, buf + bwritten, optlen);
1887 bwritten += optlen;
1888 bleft -= optlen;
1889 flags &= ~optp->o_opt;
1890 }
1891
1892 /*
1893 * Space already reserved for trailing \0
1894 */
1895 buf[bwritten] = 0;
1896 return (bwritten);
1897 }
1898
1899 /*
1900 * Build hash lists of net addresses and hang them off the mount point.
1901 * Called by ufs_mount() to set up the lists of export addresses.
1902 */
1903 static int
1904 vfs_hang_addrlist(struct mount *mp, struct netexport *nep,
1905 const struct export_args *argp)
1906 {
1907 struct netcred *np;
1908 struct radix_node_head *rnh;
1909 int i;
1910 struct radix_node *rn;
1911 struct sockaddr *saddr, *smask = NULL;
1912 struct domain *dom;
1913 int error;
1914
1915 if (argp->ex_addrlen == 0) {
1916 if (mp->mnt_flag & MNT_DEFEXPORTED)
1917 return (EPERM);
1918 np = &nep->ne_defexported;
1919 np->netc_exflags = argp->ex_flags;
1920 np->netc_anon = argp->ex_anon;
1921 np->netc_anon.cr_ref = 1;
1922 mp->mnt_flag |= MNT_DEFEXPORTED;
1923 return (0);
1924 }
1925
1926 if (argp->ex_addrlen < 0 || argp->ex_addrlen > MLEN)
1927 return (EINVAL);
1928 if (argp->ex_masklen < 0 || argp->ex_masklen > MLEN)
1929 return (EINVAL);
1930
1931 i = sizeof(struct netcred) + argp->ex_addrlen + argp->ex_masklen;
1932 np = (struct netcred *) kmalloc(i, M_NETADDR, M_WAITOK | M_ZERO);
1933 saddr = (struct sockaddr *) (np + 1);
1934 if ((error = copyin(argp->ex_addr, (caddr_t) saddr, argp->ex_addrlen)))
1935 goto out;
1936 if (saddr->sa_len > argp->ex_addrlen)
1937 saddr->sa_len = argp->ex_addrlen;
1938 if (argp->ex_masklen) {
1939 smask = (struct sockaddr *)((caddr_t)saddr + argp->ex_addrlen);
1940 error = copyin(argp->ex_mask, (caddr_t)smask, argp->ex_masklen);
1941 if (error)
1942 goto out;
1943 if (smask->sa_len > argp->ex_masklen)
1944 smask->sa_len = argp->ex_masklen;
1945 }
1946 i = saddr->sa_family;
1947 if ((rnh = nep->ne_rtable[i]) == NULL) {
1948 /*
1949 * Seems silly to initialize every AF when most are not used,
1950 * do so on demand here
1951 */
1952 SLIST_FOREACH(dom, &domains, dom_next)
1953 if (dom->dom_family == i && dom->dom_rtattach) {
1954 dom->dom_rtattach((void **) &nep->ne_rtable[i],
1955 dom->dom_rtoffset);
1956 break;
1957 }
1958 if ((rnh = nep->ne_rtable[i]) == NULL) {
1959 error = ENOBUFS;
1960 goto out;
1961 }
1962 }
1963 rn = (*rnh->rnh_addaddr) ((char *) saddr, (char *) smask, rnh,
1964 np->netc_rnodes);
1965 if (rn == NULL || np != (struct netcred *) rn) { /* already exists */
1966 error = EPERM;
1967 goto out;
1968 }
1969 np->netc_exflags = argp->ex_flags;
1970 np->netc_anon = argp->ex_anon;
1971 np->netc_anon.cr_ref = 1;
1972 return (0);
1973 out:
1974 kfree(np, M_NETADDR);
1975 return (error);
1976 }
1977
1978 /* ARGSUSED */
1979 static int
1980 vfs_free_netcred(struct radix_node *rn, void *w)
1981 {
1982 struct radix_node_head *rnh = (struct radix_node_head *) w;
1983
1984 (*rnh->rnh_deladdr) (rn->rn_key, rn->rn_mask, rnh);
1985 kfree((caddr_t) rn, M_NETADDR);
1986 return (0);
1987 }
1988
1989 /*
1990 * Free the net address hash lists that are hanging off the mount points.
1991 */
1992 static void
1993 vfs_free_addrlist(struct netexport *nep)
1994 {
1995 int i;
1996 struct radix_node_head *rnh;
1997
1998 for (i = 0; i <= AF_MAX; i++)
1999 if ((rnh = nep->ne_rtable[i])) {
2000 (*rnh->rnh_walktree) (rnh, vfs_free_netcred,
2001 (caddr_t) rnh);
2002 kfree((caddr_t) rnh, M_RTABLE);
2003 nep->ne_rtable[i] = 0;
2004 }
2005 }
2006
2007 int
2008 vfs_export(struct mount *mp, struct netexport *nep,
2009 const struct export_args *argp)
2010 {
2011 int error;
2012
2013 if (argp->ex_flags & MNT_DELEXPORT) {
2014 if (mp->mnt_flag & MNT_EXPUBLIC) {
2015 vfs_setpublicfs(NULL, NULL, NULL);
2016 mp->mnt_flag &= ~MNT_EXPUBLIC;
2017 }
2018 vfs_free_addrlist(nep);
2019 mp->mnt_flag &= ~(MNT_EXPORTED | MNT_DEFEXPORTED);
2020 }
2021 if (argp->ex_flags & MNT_EXPORTED) {
2022 if (argp->ex_flags & MNT_EXPUBLIC) {
2023 if ((error = vfs_setpublicfs(mp, nep, argp)) != 0)
2024 return (error);
2025 mp->mnt_flag |= MNT_EXPUBLIC;
2026 }
2027 if ((error = vfs_hang_addrlist(mp, nep, argp)))
2028 return (error);
2029 mp->mnt_flag |= MNT_EXPORTED;
2030 }
2031 return (0);
2032 }
2033
2034
2035 /*
2036 * Set the publicly exported filesystem (WebNFS). Currently, only
2037 * one public filesystem is possible in the spec (RFC 2054 and 2055)
2038 */
2039 int
2040 vfs_setpublicfs(struct mount *mp, struct netexport *nep,
2041 const struct export_args *argp)
2042 {
2043 int error;
2044 struct vnode *rvp;
2045 char *cp;
2046
2047 /*
2048 * mp == NULL -> invalidate the current info, the FS is
2049 * no longer exported. May be called from either vfs_export
2050 * or unmount, so check if it hasn't already been done.
2051 */
2052 if (mp == NULL) {
2053 if (nfs_pub.np_valid) {
2054 nfs_pub.np_valid = 0;
2055 if (nfs_pub.np_index != NULL) {
2056 kfree(nfs_pub.np_index, M_TEMP);
2057 nfs_pub.np_index = NULL;
2058 }
2059 }
2060 return (0);
2061 }
2062
2063 /*
2064 * Only one allowed at a time.
2065 */
2066 if (nfs_pub.np_valid != 0 && mp != nfs_pub.np_mount)
2067 return (EBUSY);
2068
2069 /*
2070 * Get real filehandle for root of exported FS.
2071 */
2072 bzero((caddr_t)&nfs_pub.np_handle, sizeof(nfs_pub.np_handle));
2073 nfs_pub.np_handle.fh_fsid = mp->mnt_stat.f_fsid;
2074
2075 if ((error = VFS_ROOT(mp, &rvp)))
2076 return (error);
2077
2078 if ((error = VFS_VPTOFH(rvp, &nfs_pub.np_handle.fh_fid)))
2079 return (error);
2080
2081 vput(rvp);
2082
2083 /*
2084 * If an indexfile was specified, pull it in.
2085 */
2086 if (argp->ex_indexfile != NULL) {
2087 int namelen;
2088
2089 error = vn_get_namelen(rvp, &namelen);
2090 if (error)
2091 return (error);
2092 nfs_pub.np_index = kmalloc(namelen, M_TEMP, M_WAITOK);
2093 error = copyinstr(argp->ex_indexfile, nfs_pub.np_index,
2094 namelen, NULL);
2095 if (!error) {
2096 /*
2097 * Check for illegal filenames.
2098 */
2099 for (cp = nfs_pub.np_index; *cp; cp++) {
2100 if (*cp == '/') {
2101 error = EINVAL;
2102 break;
2103 }
2104 }
2105 }
2106 if (error) {
2107 kfree(nfs_pub.np_index, M_TEMP);
2108 return (error);
2109 }
2110 }
2111
2112 nfs_pub.np_mount = mp;
2113 nfs_pub.np_valid = 1;
2114 return (0);
2115 }
2116
2117 struct netcred *
2118 vfs_export_lookup(struct mount *mp, struct netexport *nep,
2119 struct sockaddr *nam)
2120 {
2121 struct netcred *np;
2122 struct radix_node_head *rnh;
2123 struct sockaddr *saddr;
2124
2125 np = NULL;
2126 if (mp->mnt_flag & MNT_EXPORTED) {
2127 /*
2128 * Lookup in the export list first.
2129 */
2130 if (nam != NULL) {
2131 saddr = nam;
2132 rnh = nep->ne_rtable[saddr->sa_family];
2133 if (rnh != NULL) {
2134 np = (struct netcred *)
2135 (*rnh->rnh_matchaddr)((char *)saddr,
2136 rnh);
2137 if (np && np->netc_rnodes->rn_flags & RNF_ROOT)
2138 np = NULL;
2139 }
2140 }
2141 /*
2142 * If no address match, use the default if it exists.
2143 */
2144 if (np == NULL && mp->mnt_flag & MNT_DEFEXPORTED)
2145 np = &nep->ne_defexported;
2146 }
2147 return (np);
2148 }
2149
2150 /*
2151 * perform msync on all vnodes under a mount point. The mount point must
2152 * be locked. This code is also responsible for lazy-freeing unreferenced
2153 * vnodes whos VM objects no longer contain pages.
2154 *
2155 * NOTE: MNT_WAIT still skips vnodes in the VXLOCK state.
2156 *
2157 * NOTE: XXX VOP_PUTPAGES and friends requires that the vnode be locked,
2158 * but vnode_pager_putpages() doesn't lock the vnode. We have to do it
2159 * way up in this high level function.
2160 */
2161 static int vfs_msync_scan1(struct mount *mp, struct vnode *vp, void *data);
2162 static int vfs_msync_scan2(struct mount *mp, struct vnode *vp, void *data);
2163
2164 void
2165 vfs_msync(struct mount *mp, int flags)
2166 {
2167 int vmsc_flags;
2168
2169 /*
2170 * tmpfs sets this flag to prevent msync(), sync, and the
2171 * filesystem periodic syncer from trying to flush VM pages
2172 * to swap. Only pure memory pressure flushes tmpfs VM pages
2173 * to swap.
2174 */
2175 if (mp->mnt_kern_flag & MNTK_NOMSYNC)
2176 return;
2177
2178 /*
2179 * Ok, scan the vnodes for work. If the filesystem is using the
2180 * syncer thread feature we can use vsyncscan() instead of
2181 * vmntvnodescan(), which is much faster.
2182 */
2183 vmsc_flags = VMSC_GETVP;
2184 if (flags != MNT_WAIT)
2185 vmsc_flags |= VMSC_NOWAIT;
2186
2187 if (mp->mnt_kern_flag & MNTK_THR_SYNC) {
2188 vsyncscan(mp, vmsc_flags, vfs_msync_scan2,
2189 (void *)(intptr_t)flags);
2190 } else {
2191 vmntvnodescan(mp, vmsc_flags,
2192 vfs_msync_scan1, vfs_msync_scan2,
2193 (void *)(intptr_t)flags);
2194 }
2195 }
2196
2197 /*
2198 * scan1 is a fast pre-check. There could be hundreds of thousands of
2199 * vnodes, we cannot afford to do anything heavy weight until we have a
2200 * fairly good indication that there is work to do.
2201 */
2202 static
2203 int
2204 vfs_msync_scan1(struct mount *mp, struct vnode *vp, void *data)
2205 {
2206 int flags = (int)(intptr_t)data;
2207
2208 if ((vp->v_flag & VRECLAIMED) == 0) {
2209 if (vp->v_auxrefs == 0 && VREFCNT(vp) <= 0 &&
2210 vp->v_object) {
2211 return(0); /* call scan2 */
2212 }
2213 if ((mp->mnt_flag & MNT_RDONLY) == 0 &&
2214 (vp->v_flag & VOBJDIRTY) &&
2215 (flags == MNT_WAIT || vn_islocked(vp) == 0)) {
2216 return(0); /* call scan2 */
2217 }
2218 }
2219
2220 /*
2221 * do not call scan2, continue the loop
2222 */
2223 return(-1);
2224 }
2225
2226 /*
2227 * This callback is handed a locked vnode.
2228 */
2229 static
2230 int
2231 vfs_msync_scan2(struct mount *mp, struct vnode *vp, void *data)
2232 {
2233 vm_object_t obj;
2234 int flags = (int)(intptr_t)data;
2235
2236 if (vp->v_flag & VRECLAIMED)
2237 return(0);
2238
2239 if ((mp->mnt_flag & MNT_RDONLY) == 0 && (vp->v_flag & VOBJDIRTY)) {
2240 if ((obj = vp->v_object) != NULL) {
2241 vm_object_page_clean(obj, 0, 0,
2242 flags == MNT_WAIT ? OBJPC_SYNC : OBJPC_NOSYNC);
2243 }
2244 }
2245 return(0);
2246 }
2247
2248 /*
2249 * Wake up anyone interested in vp because it is being revoked.
2250 */
2251 void
2252 vn_gone(struct vnode *vp)
2253 {
2254 lwkt_gettoken(&vp->v_token);
2255 KNOTE(&vp->v_pollinfo.vpi_kqinfo.ki_note, NOTE_REVOKE);
2256 lwkt_reltoken(&vp->v_token);
2257 }
2258
2259 /*
2260 * extract the cdev_t from a VBLK or VCHR. The vnode must have been opened
2261 * (or v_rdev might be NULL).
2262 */
2263 cdev_t
2264 vn_todev(struct vnode *vp)
2265 {
2266 if (vp->v_type != VBLK && vp->v_type != VCHR)
2267 return (NULL);
2268 KKASSERT(vp->v_rdev != NULL);
2269 return (vp->v_rdev);
2270 }
2271
2272 /*
2273 * Check if vnode represents a disk device. The vnode does not need to be
2274 * opened.
2275 *
2276 * MPALMOSTSAFE
2277 */
2278 int
2279 vn_isdisk(struct vnode *vp, int *errp)
2280 {
2281 cdev_t dev;
2282
2283 if (vp->v_type != VCHR) {
2284 if (errp != NULL)
2285 *errp = ENOTBLK;
2286 return (0);
2287 }
2288
2289 dev = vp->v_rdev;
2290
2291 if (dev == NULL) {
2292 if (errp != NULL)
2293 *errp = ENXIO;
2294 return (0);
2295 }
2296 if (dev_is_good(dev) == 0) {
2297 if (errp != NULL)
2298 *errp = ENXIO;
2299 return (0);
2300 }
2301 if ((dev_dflags(dev) & D_DISK) == 0) {
2302 if (errp != NULL)
2303 *errp = ENOTBLK;
2304 return (0);
2305 }
2306 if (errp != NULL)
2307 *errp = 0;
2308 return (1);
2309 }
2310
2311 int
2312 vn_get_namelen(struct vnode *vp, int *namelen)
2313 {
2314 int error;
2315 register_t retval[2];
2316
2317 error = VOP_PATHCONF(vp, _PC_NAME_MAX, retval);
2318 if (error)
2319 return (error);
2320 *namelen = (int)retval[0];
2321 return (0);
2322 }
2323
2324 int
2325 vop_write_dirent(int *error, struct uio *uio, ino_t d_ino, uint8_t d_type,
2326 uint16_t d_namlen, const char *d_name)
2327 {
2328 struct dirent *dp;
2329 size_t len;
2330
2331 len = _DIRENT_RECLEN(d_namlen);
2332 if (len > uio->uio_resid)
2333 return(1);
2334
2335 dp = kmalloc(len, M_TEMP, M_WAITOK | M_ZERO);
2336
2337 dp->d_ino = d_ino;
2338 dp->d_namlen = d_namlen;
2339 dp->d_type = d_type;
2340 bcopy(d_name, dp->d_name, d_namlen);
2341
2342 *error = uiomove((caddr_t)dp, len, uio);
2343
2344 kfree(dp, M_TEMP);
2345
2346 return(0);
2347 }
2348
2349 void
2350 vn_mark_atime(struct vnode *vp, struct thread *td)
2351 {
2352 struct proc *p = td->td_proc;
2353 struct ucred *cred = p ? p->p_ucred : proc0.p_ucred;
2354
2355 if ((vp->v_mount->mnt_flag & (MNT_NOATIME | MNT_RDONLY)) == 0) {
2356 VOP_MARKATIME(vp, cred);
2357 }
2358 }
Cache object: 33e21ea0bc28117d2299e985d8a42768
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