Commit | Line | Data |
---|---|---|
3c4390e8 KM |
1 | /* |
2 | * Copyright (c) 1989 The Regents of the University of California. | |
3 | * All rights reserved. | |
4 | * | |
dbf0c423 | 5 | * %sccs.include.redist.c% |
3c4390e8 | 6 | * |
8136adfc | 7 | * @(#)vfs_subr.c 7.59 (Berkeley) %G% |
3c4390e8 KM |
8 | */ |
9 | ||
10 | /* | |
11 | * External virtual filesystem routines | |
12 | */ | |
13 | ||
14 | #include "param.h" | |
c099667a | 15 | #include "proc.h" |
3c4390e8 KM |
16 | #include "mount.h" |
17 | #include "time.h" | |
18 | #include "vnode.h" | |
0f93ba7b | 19 | #include "specdev.h" |
c60798ca KM |
20 | #include "namei.h" |
21 | #include "ucred.h" | |
76429560 | 22 | #include "buf.h" |
3c4390e8 | 23 | #include "errno.h" |
ef24f6dd | 24 | #include "malloc.h" |
3c4390e8 | 25 | |
3c4390e8 KM |
26 | /* |
27 | * Remove a mount point from the list of mounted filesystems. | |
28 | * Unmount of the root is illegal. | |
29 | */ | |
30 | void | |
31 | vfs_remove(mp) | |
32 | register struct mount *mp; | |
33 | { | |
34 | ||
35 | if (mp == rootfs) | |
36 | panic("vfs_remove: unmounting root"); | |
54fb9dc2 KM |
37 | mp->mnt_prev->mnt_next = mp->mnt_next; |
38 | mp->mnt_next->mnt_prev = mp->mnt_prev; | |
39 | mp->mnt_vnodecovered->v_mountedhere = (struct mount *)0; | |
3c4390e8 KM |
40 | vfs_unlock(mp); |
41 | } | |
42 | ||
43 | /* | |
44 | * Lock a filesystem. | |
45 | * Used to prevent access to it while mounting and unmounting. | |
46 | */ | |
47 | vfs_lock(mp) | |
48 | register struct mount *mp; | |
49 | { | |
50 | ||
54fb9dc2 KM |
51 | while(mp->mnt_flag & MNT_MLOCK) { |
52 | mp->mnt_flag |= MNT_MWAIT; | |
594501df KM |
53 | sleep((caddr_t)mp, PVFS); |
54 | } | |
54fb9dc2 | 55 | mp->mnt_flag |= MNT_MLOCK; |
3c4390e8 KM |
56 | return (0); |
57 | } | |
58 | ||
59 | /* | |
60 | * Unlock a locked filesystem. | |
61 | * Panic if filesystem is not locked. | |
62 | */ | |
63 | void | |
64 | vfs_unlock(mp) | |
65 | register struct mount *mp; | |
66 | { | |
67 | ||
54fb9dc2 | 68 | if ((mp->mnt_flag & MNT_MLOCK) == 0) |
36ef03ec | 69 | panic("vfs_unlock: not locked"); |
54fb9dc2 KM |
70 | mp->mnt_flag &= ~MNT_MLOCK; |
71 | if (mp->mnt_flag & MNT_MWAIT) { | |
72 | mp->mnt_flag &= ~MNT_MWAIT; | |
3c4390e8 KM |
73 | wakeup((caddr_t)mp); |
74 | } | |
75 | } | |
76 | ||
36ef03ec KM |
77 | /* |
78 | * Mark a mount point as busy. | |
79 | * Used to synchronize access and to delay unmounting. | |
80 | */ | |
81 | vfs_busy(mp) | |
82 | register struct mount *mp; | |
83 | { | |
84 | ||
54fb9dc2 KM |
85 | while(mp->mnt_flag & MNT_MPBUSY) { |
86 | mp->mnt_flag |= MNT_MPWANT; | |
87 | sleep((caddr_t)&mp->mnt_flag, PVFS); | |
36ef03ec | 88 | } |
d8b63609 KM |
89 | if (mp->mnt_flag & MNT_UNMOUNT) |
90 | return (1); | |
54fb9dc2 | 91 | mp->mnt_flag |= MNT_MPBUSY; |
36ef03ec KM |
92 | return (0); |
93 | } | |
94 | ||
95 | /* | |
96 | * Free a busy filesystem. | |
97 | * Panic if filesystem is not busy. | |
98 | */ | |
36ef03ec KM |
99 | vfs_unbusy(mp) |
100 | register struct mount *mp; | |
101 | { | |
102 | ||
54fb9dc2 | 103 | if ((mp->mnt_flag & MNT_MPBUSY) == 0) |
36ef03ec | 104 | panic("vfs_unbusy: not busy"); |
54fb9dc2 KM |
105 | mp->mnt_flag &= ~MNT_MPBUSY; |
106 | if (mp->mnt_flag & MNT_MPWANT) { | |
107 | mp->mnt_flag &= ~MNT_MPWANT; | |
108 | wakeup((caddr_t)&mp->mnt_flag); | |
36ef03ec KM |
109 | } |
110 | } | |
111 | ||
3c4390e8 KM |
112 | /* |
113 | * Lookup a mount point by filesystem identifier. | |
114 | */ | |
115 | struct mount * | |
116 | getvfs(fsid) | |
117 | fsid_t *fsid; | |
118 | { | |
119 | register struct mount *mp; | |
120 | ||
d713f801 KM |
121 | mp = rootfs; |
122 | do { | |
54fb9dc2 KM |
123 | if (mp->mnt_stat.f_fsid.val[0] == fsid->val[0] && |
124 | mp->mnt_stat.f_fsid.val[1] == fsid->val[1]) { | |
d713f801 | 125 | return (mp); |
3c4390e8 | 126 | } |
54fb9dc2 | 127 | mp = mp->mnt_next; |
d713f801 KM |
128 | } while (mp != rootfs); |
129 | return ((struct mount *)0); | |
3c4390e8 KM |
130 | } |
131 | ||
132 | /* | |
133 | * Set vnode attributes to VNOVAL | |
134 | */ | |
135 | void vattr_null(vap) | |
136 | register struct vattr *vap; | |
137 | { | |
138 | ||
139 | vap->va_type = VNON; | |
140 | vap->va_mode = vap->va_nlink = vap->va_uid = vap->va_gid = | |
141 | vap->va_fsid = vap->va_fileid = vap->va_size = | |
8fae943a KM |
142 | vap->va_size_rsv = vap->va_blocksize = vap->va_rdev = |
143 | vap->va_bytes = vap->va_bytes_rsv = | |
3c4390e8 KM |
144 | vap->va_atime.tv_sec = vap->va_atime.tv_usec = |
145 | vap->va_mtime.tv_sec = vap->va_mtime.tv_usec = | |
8cf4d4fb KM |
146 | vap->va_ctime.tv_sec = vap->va_ctime.tv_usec = |
147 | vap->va_flags = vap->va_gen = VNOVAL; | |
3c4390e8 | 148 | } |
c60798ca | 149 | |
36d09cb1 KM |
150 | /* |
151 | * Routines having to do with the management of the vnode table. | |
152 | */ | |
153 | struct vnode *vfreeh, **vfreet; | |
4ef5d036 | 154 | extern struct vnodeops dead_vnodeops, spec_vnodeops; |
32339c94 | 155 | extern void vclean(); |
1a80f56e | 156 | long numvnodes; |
d3664d8f | 157 | struct vattr va_null; |
c0de8792 | 158 | |
36d09cb1 | 159 | /* |
ef24f6dd | 160 | * Initialize the vnode structures and initialize each file system type. |
36d09cb1 | 161 | */ |
ef24f6dd | 162 | vfsinit() |
36d09cb1 | 163 | { |
ef24f6dd | 164 | struct vfsops **vfsp; |
36d09cb1 | 165 | |
ef24f6dd KM |
166 | /* |
167 | * Initialize the vnode name cache | |
168 | */ | |
169 | nchinit(); | |
170 | /* | |
171 | * Initialize each file system type. | |
172 | */ | |
d3664d8f | 173 | vattr_null(&va_null); |
ef24f6dd KM |
174 | for (vfsp = &vfssw[0]; vfsp <= &vfssw[MOUNT_MAXTYPE]; vfsp++) { |
175 | if (*vfsp == NULL) | |
176 | continue; | |
177 | (*(*vfsp)->vfs_init)(); | |
178 | } | |
36d09cb1 KM |
179 | } |
180 | ||
181 | /* | |
182 | * Return the next vnode from the free list. | |
183 | */ | |
184 | getnewvnode(tag, mp, vops, vpp) | |
185 | enum vtagtype tag; | |
186 | struct mount *mp; | |
187 | struct vnodeops *vops; | |
188 | struct vnode **vpp; | |
189 | { | |
190 | register struct vnode *vp, *vq; | |
191 | ||
1a80f56e | 192 | if (numvnodes < desiredvnodes) { |
aacc1bff KM |
193 | vp = (struct vnode *)malloc((u_long)sizeof *vp, |
194 | M_VNODE, M_WAITOK); | |
1a80f56e KM |
195 | bzero((char *)vp, sizeof *vp); |
196 | numvnodes++; | |
197 | } else { | |
198 | if ((vp = vfreeh) == NULL) { | |
199 | tablefull("vnode"); | |
200 | *vpp = 0; | |
201 | return (ENFILE); | |
202 | } | |
203 | if (vp->v_usecount) | |
204 | panic("free vnode isn't"); | |
205 | if (vq = vp->v_freef) | |
206 | vq->v_freeb = &vfreeh; | |
207 | else | |
208 | vfreet = &vfreeh; | |
209 | vfreeh = vq; | |
210 | vp->v_freef = NULL; | |
211 | vp->v_freeb = NULL; | |
212 | if (vp->v_type != VBAD) | |
213 | vgone(vp); | |
214 | vp->v_flag = 0; | |
1a80f56e KM |
215 | vp->v_lastr = 0; |
216 | vp->v_socket = 0; | |
36d09cb1 | 217 | } |
b027498b | 218 | vp->v_type = VNON; |
36d09cb1 KM |
219 | cache_purge(vp); |
220 | vp->v_tag = tag; | |
ef24f6dd | 221 | vp->v_op = vops; |
36d09cb1 KM |
222 | insmntque(vp, mp); |
223 | VREF(vp); | |
224 | *vpp = vp; | |
225 | return (0); | |
226 | } | |
227 | ||
228 | /* | |
229 | * Move a vnode from one mount queue to another. | |
230 | */ | |
231 | insmntque(vp, mp) | |
232 | register struct vnode *vp; | |
233 | register struct mount *mp; | |
234 | { | |
8136adfc | 235 | register struct vnode *vq; |
36d09cb1 KM |
236 | |
237 | /* | |
238 | * Delete from old mount point vnode list, if on one. | |
239 | */ | |
240 | if (vp->v_mountb) { | |
241 | if (vq = vp->v_mountf) | |
242 | vq->v_mountb = vp->v_mountb; | |
243 | *vp->v_mountb = vq; | |
244 | } | |
245 | /* | |
246 | * Insert into list of vnodes for the new mount point, if available. | |
247 | */ | |
a45ff315 | 248 | vp->v_mount = mp; |
36d09cb1 KM |
249 | if (mp == NULL) { |
250 | vp->v_mountf = NULL; | |
251 | vp->v_mountb = NULL; | |
252 | return; | |
253 | } | |
8136adfc KM |
254 | if (vq = mp->mnt_mounth) |
255 | vq->v_mountb = &vp->v_mountf; | |
256 | vp->v_mountf = vq; | |
257 | vp->v_mountb = &mp->mnt_mounth; | |
258 | mp->mnt_mounth = vp; | |
36d09cb1 KM |
259 | } |
260 | ||
76429560 KM |
261 | /* |
262 | * Make sure all write-behind blocks associated | |
263 | * with mount point are flushed out (from sync). | |
264 | */ | |
265 | mntflushbuf(mountp, flags) | |
266 | struct mount *mountp; | |
267 | int flags; | |
268 | { | |
269 | register struct vnode *vp; | |
270 | ||
271 | if ((mountp->mnt_flag & MNT_MPBUSY) == 0) | |
272 | panic("mntflushbuf: not busy"); | |
273 | loop: | |
274 | for (vp = mountp->mnt_mounth; vp; vp = vp->v_mountf) { | |
275 | if (VOP_ISLOCKED(vp)) | |
276 | continue; | |
277 | if (vget(vp)) | |
278 | goto loop; | |
279 | vflushbuf(vp, flags); | |
280 | vput(vp); | |
281 | if (vp->v_mount != mountp) | |
282 | goto loop; | |
283 | } | |
284 | } | |
285 | ||
286 | /* | |
287 | * Flush all dirty buffers associated with a vnode. | |
288 | */ | |
289 | vflushbuf(vp, flags) | |
290 | register struct vnode *vp; | |
291 | int flags; | |
292 | { | |
293 | register struct buf *bp; | |
294 | struct buf *nbp; | |
295 | int s; | |
296 | ||
297 | loop: | |
298 | s = splbio(); | |
299 | for (bp = vp->v_dirtyblkhd; bp; bp = nbp) { | |
300 | nbp = bp->b_blockf; | |
301 | if ((bp->b_flags & B_BUSY)) | |
302 | continue; | |
303 | if ((bp->b_flags & B_DELWRI) == 0) | |
304 | panic("vflushbuf: not dirty"); | |
305 | bremfree(bp); | |
306 | bp->b_flags |= B_BUSY; | |
307 | splx(s); | |
308 | /* | |
309 | * Wait for I/O associated with indirect blocks to complete, | |
310 | * since there is no way to quickly wait for them below. | |
311 | * NB: This is really specific to ufs, but is done here | |
312 | * as it is easier and quicker. | |
313 | */ | |
77dc8a8c | 314 | if (bp->b_vp == vp || (flags & B_SYNC) == 0) |
76429560 | 315 | (void) bawrite(bp); |
77dc8a8c | 316 | else |
76429560 | 317 | (void) bwrite(bp); |
77dc8a8c | 318 | goto loop; |
76429560 KM |
319 | } |
320 | splx(s); | |
321 | if ((flags & B_SYNC) == 0) | |
322 | return; | |
323 | s = splbio(); | |
324 | while (vp->v_numoutput) { | |
325 | vp->v_flag |= VBWAIT; | |
326 | sleep((caddr_t)&vp->v_numoutput, PRIBIO + 1); | |
327 | } | |
328 | splx(s); | |
329 | if (vp->v_dirtyblkhd) { | |
330 | vprint("vflushbuf: dirty", vp); | |
331 | goto loop; | |
332 | } | |
333 | } | |
334 | ||
335 | /* | |
336 | * Update outstanding I/O count and do wakeup if requested. | |
337 | */ | |
338 | vwakeup(bp) | |
339 | register struct buf *bp; | |
340 | { | |
341 | register struct vnode *vp; | |
342 | ||
343 | bp->b_dirtyoff = bp->b_dirtyend = 0; | |
344 | if (vp = bp->b_vp) { | |
345 | vp->v_numoutput--; | |
346 | if ((vp->v_flag & VBWAIT) && vp->v_numoutput <= 0) { | |
347 | if (vp->v_numoutput < 0) | |
348 | panic("vwakeup: neg numoutput"); | |
349 | vp->v_flag &= ~VBWAIT; | |
350 | wakeup((caddr_t)&vp->v_numoutput); | |
351 | } | |
352 | } | |
353 | } | |
354 | ||
355 | /* | |
356 | * Invalidate in core blocks belonging to closed or umounted filesystem | |
357 | * | |
358 | * Go through the list of vnodes associated with the file system; | |
359 | * for each vnode invalidate any buffers that it holds. Normally | |
360 | * this routine is preceeded by a bflush call, so that on a quiescent | |
361 | * filesystem there will be no dirty buffers when we are done. Binval | |
362 | * returns the count of dirty buffers when it is finished. | |
363 | */ | |
364 | mntinvalbuf(mountp) | |
365 | struct mount *mountp; | |
366 | { | |
367 | register struct vnode *vp; | |
368 | int dirty = 0; | |
369 | ||
370 | if ((mountp->mnt_flag & MNT_MPBUSY) == 0) | |
371 | panic("mntinvalbuf: not busy"); | |
372 | loop: | |
373 | for (vp = mountp->mnt_mounth; vp; vp = vp->v_mountf) { | |
374 | if (vget(vp)) | |
375 | goto loop; | |
376 | dirty += vinvalbuf(vp, 1); | |
377 | vput(vp); | |
378 | if (vp->v_mount != mountp) | |
379 | goto loop; | |
380 | } | |
381 | return (dirty); | |
382 | } | |
383 | ||
384 | /* | |
385 | * Flush out and invalidate all buffers associated with a vnode. | |
386 | * Called with the underlying object locked. | |
387 | */ | |
388 | vinvalbuf(vp, save) | |
389 | register struct vnode *vp; | |
390 | int save; | |
391 | { | |
392 | register struct buf *bp; | |
393 | struct buf *nbp, *blist; | |
394 | int s, dirty = 0; | |
395 | ||
396 | for (;;) { | |
397 | if (blist = vp->v_dirtyblkhd) | |
398 | /* void */; | |
399 | else if (blist = vp->v_cleanblkhd) | |
400 | /* void */; | |
401 | else | |
402 | break; | |
403 | for (bp = blist; bp; bp = nbp) { | |
404 | nbp = bp->b_blockf; | |
405 | s = splbio(); | |
406 | if (bp->b_flags & B_BUSY) { | |
407 | bp->b_flags |= B_WANTED; | |
408 | sleep((caddr_t)bp, PRIBIO + 1); | |
409 | splx(s); | |
410 | break; | |
411 | } | |
412 | bremfree(bp); | |
413 | bp->b_flags |= B_BUSY; | |
414 | splx(s); | |
415 | if (save && (bp->b_flags & B_DELWRI)) { | |
416 | dirty++; | |
417 | (void) bwrite(bp); | |
418 | break; | |
419 | } | |
420 | if (bp->b_vp != vp) | |
421 | reassignbuf(bp, bp->b_vp); | |
422 | else | |
423 | bp->b_flags |= B_INVAL; | |
424 | brelse(bp); | |
425 | } | |
426 | } | |
427 | if (vp->v_dirtyblkhd || vp->v_cleanblkhd) | |
428 | panic("vinvalbuf: flush failed"); | |
429 | return (dirty); | |
430 | } | |
431 | ||
432 | /* | |
433 | * Associate a buffer with a vnode. | |
434 | */ | |
435 | bgetvp(vp, bp) | |
436 | register struct vnode *vp; | |
437 | register struct buf *bp; | |
438 | { | |
8136adfc KM |
439 | register struct vnode *vq; |
440 | register struct buf *bq; | |
76429560 KM |
441 | |
442 | if (bp->b_vp) | |
443 | panic("bgetvp: not free"); | |
444 | VHOLD(vp); | |
445 | bp->b_vp = vp; | |
446 | if (vp->v_type == VBLK || vp->v_type == VCHR) | |
447 | bp->b_dev = vp->v_rdev; | |
448 | else | |
449 | bp->b_dev = NODEV; | |
450 | /* | |
451 | * Insert onto list for new vnode. | |
452 | */ | |
8136adfc KM |
453 | if (bq = vp->v_cleanblkhd) |
454 | bq->b_blockb = &bp->b_blockf; | |
455 | bp->b_blockf = bq; | |
456 | bp->b_blockb = &vp->v_cleanblkhd; | |
457 | vp->v_cleanblkhd = bp; | |
76429560 KM |
458 | } |
459 | ||
460 | /* | |
461 | * Disassociate a buffer from a vnode. | |
462 | */ | |
463 | brelvp(bp) | |
464 | register struct buf *bp; | |
465 | { | |
466 | struct buf *bq; | |
467 | struct vnode *vp; | |
468 | ||
469 | if (bp->b_vp == (struct vnode *) 0) | |
470 | panic("brelvp: NULL"); | |
471 | /* | |
472 | * Delete from old vnode list, if on one. | |
473 | */ | |
474 | if (bp->b_blockb) { | |
475 | if (bq = bp->b_blockf) | |
476 | bq->b_blockb = bp->b_blockb; | |
477 | *bp->b_blockb = bq; | |
478 | bp->b_blockf = NULL; | |
479 | bp->b_blockb = NULL; | |
480 | } | |
481 | vp = bp->b_vp; | |
482 | bp->b_vp = (struct vnode *) 0; | |
483 | HOLDRELE(vp); | |
484 | } | |
485 | ||
486 | /* | |
487 | * Reassign a buffer from one vnode to another. | |
488 | * Used to assign file specific control information | |
489 | * (indirect blocks) to the vnode to which they belong. | |
490 | */ | |
491 | reassignbuf(bp, newvp) | |
492 | register struct buf *bp; | |
493 | register struct vnode *newvp; | |
494 | { | |
495 | register struct buf *bq, **listheadp; | |
496 | ||
497 | if (newvp == NULL) | |
498 | panic("reassignbuf: NULL"); | |
499 | /* | |
500 | * Delete from old vnode list, if on one. | |
501 | */ | |
502 | if (bp->b_blockb) { | |
503 | if (bq = bp->b_blockf) | |
504 | bq->b_blockb = bp->b_blockb; | |
505 | *bp->b_blockb = bq; | |
506 | } | |
507 | /* | |
508 | * If dirty, put on list of dirty buffers; | |
509 | * otherwise insert onto list of clean buffers. | |
510 | */ | |
511 | if (bp->b_flags & B_DELWRI) | |
512 | listheadp = &newvp->v_dirtyblkhd; | |
513 | else | |
514 | listheadp = &newvp->v_cleanblkhd; | |
8136adfc KM |
515 | if (bq = *listheadp) |
516 | bq->b_blockb = &bp->b_blockf; | |
517 | bp->b_blockf = bq; | |
518 | bp->b_blockb = listheadp; | |
519 | *listheadp = bp; | |
76429560 KM |
520 | } |
521 | ||
36d09cb1 | 522 | /* |
ef24f6dd KM |
523 | * Create a vnode for a block device. |
524 | * Used for root filesystem, argdev, and swap areas. | |
525 | * Also used for memory file system special devices. | |
526 | */ | |
527 | bdevvp(dev, vpp) | |
528 | dev_t dev; | |
529 | struct vnode **vpp; | |
530 | { | |
ef24f6dd KM |
531 | register struct vnode *vp; |
532 | struct vnode *nvp; | |
533 | int error; | |
534 | ||
1c89915d KM |
535 | if (dev == NODEV) |
536 | return (0); | |
4ef5d036 | 537 | error = getnewvnode(VT_NON, (struct mount *)0, &spec_vnodeops, &nvp); |
ef24f6dd KM |
538 | if (error) { |
539 | *vpp = 0; | |
540 | return (error); | |
541 | } | |
542 | vp = nvp; | |
543 | vp->v_type = VBLK; | |
c0de8792 | 544 | if (nvp = checkalias(vp, dev, (struct mount *)0)) { |
ef24f6dd KM |
545 | vput(vp); |
546 | vp = nvp; | |
547 | } | |
548 | *vpp = vp; | |
549 | return (0); | |
550 | } | |
551 | ||
552 | /* | |
553 | * Check to see if the new vnode represents a special device | |
554 | * for which we already have a vnode (either because of | |
555 | * bdevvp() or because of a different vnode representing | |
556 | * the same block device). If such an alias exists, deallocate | |
f0556f86 | 557 | * the existing contents and return the aliased vnode. The |
ef24f6dd KM |
558 | * caller is responsible for filling it with its new contents. |
559 | */ | |
560 | struct vnode * | |
c0de8792 | 561 | checkalias(nvp, nvp_rdev, mp) |
ef24f6dd | 562 | register struct vnode *nvp; |
c0de8792 | 563 | dev_t nvp_rdev; |
ef24f6dd KM |
564 | struct mount *mp; |
565 | { | |
566 | register struct vnode *vp; | |
c0de8792 | 567 | struct vnode **vpp; |
ef24f6dd KM |
568 | |
569 | if (nvp->v_type != VBLK && nvp->v_type != VCHR) | |
54fb9dc2 | 570 | return (NULLVP); |
c0de8792 KM |
571 | |
572 | vpp = &speclisth[SPECHASH(nvp_rdev)]; | |
ef24f6dd | 573 | loop: |
c0de8792 KM |
574 | for (vp = *vpp; vp; vp = vp->v_specnext) { |
575 | if (nvp_rdev != vp->v_rdev || nvp->v_type != vp->v_type) | |
ef24f6dd | 576 | continue; |
c0de8792 KM |
577 | /* |
578 | * Alias, but not in use, so flush it out. | |
579 | */ | |
7f7b7d89 | 580 | if (vp->v_usecount == 0) { |
c0de8792 KM |
581 | vgone(vp); |
582 | goto loop; | |
583 | } | |
ef62830d KM |
584 | if (vget(vp)) |
585 | goto loop; | |
ef24f6dd KM |
586 | break; |
587 | } | |
c0de8792 | 588 | if (vp == NULL || vp->v_tag != VT_NON) { |
c0de8792 KM |
589 | MALLOC(nvp->v_specinfo, struct specinfo *, |
590 | sizeof(struct specinfo), M_VNODE, M_WAITOK); | |
591 | nvp->v_rdev = nvp_rdev; | |
7f7b7d89 | 592 | nvp->v_hashchain = vpp; |
c0de8792 | 593 | nvp->v_specnext = *vpp; |
2c957a90 | 594 | nvp->v_specflags = 0; |
c0de8792 | 595 | *vpp = nvp; |
40452d5e KM |
596 | if (vp != NULL) { |
597 | nvp->v_flag |= VALIASED; | |
598 | vp->v_flag |= VALIASED; | |
599 | vput(vp); | |
600 | } | |
54fb9dc2 | 601 | return (NULLVP); |
ef24f6dd | 602 | } |
2bae1875 KM |
603 | VOP_UNLOCK(vp); |
604 | vclean(vp, 0); | |
ef24f6dd KM |
605 | vp->v_op = nvp->v_op; |
606 | vp->v_tag = nvp->v_tag; | |
607 | nvp->v_type = VNON; | |
608 | insmntque(vp, mp); | |
609 | return (vp); | |
610 | } | |
611 | ||
612 | /* | |
613 | * Grab a particular vnode from the free list, increment its | |
614 | * reference count and lock it. The vnode lock bit is set the | |
615 | * vnode is being eliminated in vgone. The process is awakened | |
616 | * when the transition is completed, and an error returned to | |
617 | * indicate that the vnode is no longer usable (possibly having | |
618 | * been changed to a new file system type). | |
36d09cb1 KM |
619 | */ |
620 | vget(vp) | |
621 | register struct vnode *vp; | |
622 | { | |
623 | register struct vnode *vq; | |
624 | ||
ef24f6dd KM |
625 | if (vp->v_flag & VXLOCK) { |
626 | vp->v_flag |= VXWANT; | |
627 | sleep((caddr_t)vp, PINOD); | |
628 | return (1); | |
629 | } | |
7f7b7d89 | 630 | if (vp->v_usecount == 0) { |
ef24f6dd KM |
631 | if (vq = vp->v_freef) |
632 | vq->v_freeb = vp->v_freeb; | |
633 | else | |
634 | vfreet = vp->v_freeb; | |
635 | *vp->v_freeb = vq; | |
636 | vp->v_freef = NULL; | |
637 | vp->v_freeb = NULL; | |
638 | } | |
36d09cb1 | 639 | VREF(vp); |
ef24f6dd KM |
640 | VOP_LOCK(vp); |
641 | return (0); | |
36d09cb1 KM |
642 | } |
643 | ||
644 | /* | |
645 | * Vnode reference, just increment the count | |
646 | */ | |
647 | void vref(vp) | |
648 | struct vnode *vp; | |
649 | { | |
650 | ||
7f7b7d89 | 651 | vp->v_usecount++; |
36d09cb1 KM |
652 | } |
653 | ||
654 | /* | |
655 | * vput(), just unlock and vrele() | |
656 | */ | |
657 | void vput(vp) | |
658 | register struct vnode *vp; | |
659 | { | |
660 | VOP_UNLOCK(vp); | |
661 | vrele(vp); | |
662 | } | |
663 | ||
664 | /* | |
665 | * Vnode release. | |
666 | * If count drops to zero, call inactive routine and return to freelist. | |
667 | */ | |
668 | void vrele(vp) | |
669 | register struct vnode *vp; | |
670 | { | |
c099667a | 671 | struct proc *p = curproc; /* XXX */ |
36d09cb1 KM |
672 | |
673 | if (vp == NULL) | |
ef24f6dd | 674 | panic("vrele: null vp"); |
7f7b7d89 KM |
675 | vp->v_usecount--; |
676 | if (vp->v_usecount < 0) | |
0bf84b18 | 677 | vprint("vrele: bad ref count", vp); |
7f7b7d89 | 678 | if (vp->v_usecount > 0) |
36d09cb1 | 679 | return; |
54fb9dc2 | 680 | if (vfreeh == NULLVP) { |
36d09cb1 KM |
681 | /* |
682 | * insert into empty list | |
683 | */ | |
684 | vfreeh = vp; | |
685 | vp->v_freeb = &vfreeh; | |
36d09cb1 KM |
686 | } else { |
687 | /* | |
688 | * insert at tail of list | |
689 | */ | |
690 | *vfreet = vp; | |
691 | vp->v_freeb = vfreet; | |
36d09cb1 | 692 | } |
ef24f6dd KM |
693 | vp->v_freef = NULL; |
694 | vfreet = &vp->v_freef; | |
c099667a | 695 | VOP_INACTIVE(vp, p); |
ef24f6dd KM |
696 | } |
697 | ||
7f7b7d89 KM |
698 | /* |
699 | * Page or buffer structure gets a reference. | |
700 | */ | |
701 | vhold(vp) | |
702 | register struct vnode *vp; | |
703 | { | |
704 | ||
705 | vp->v_holdcnt++; | |
706 | } | |
707 | ||
708 | /* | |
709 | * Page or buffer structure frees a reference. | |
710 | */ | |
711 | holdrele(vp) | |
712 | register struct vnode *vp; | |
713 | { | |
714 | ||
715 | if (vp->v_holdcnt <= 0) | |
716 | panic("holdrele: holdcnt"); | |
717 | vp->v_holdcnt--; | |
718 | } | |
719 | ||
f0556f86 KM |
720 | /* |
721 | * Remove any vnodes in the vnode table belonging to mount point mp. | |
722 | * | |
723 | * If MNT_NOFORCE is specified, there should not be any active ones, | |
724 | * return error if any are found (nb: this is a user error, not a | |
725 | * system error). If MNT_FORCE is specified, detach any active vnodes | |
726 | * that are found. | |
727 | */ | |
728 | int busyprt = 0; /* patch to print out busy vnodes */ | |
729 | ||
730 | vflush(mp, skipvp, flags) | |
731 | struct mount *mp; | |
732 | struct vnode *skipvp; | |
733 | int flags; | |
734 | { | |
735 | register struct vnode *vp, *nvp; | |
736 | int busy = 0; | |
737 | ||
54fb9dc2 | 738 | if ((mp->mnt_flag & MNT_MPBUSY) == 0) |
36ef03ec | 739 | panic("vflush: not busy"); |
4597dd33 | 740 | loop: |
54fb9dc2 | 741 | for (vp = mp->mnt_mounth; vp; vp = nvp) { |
4597dd33 KM |
742 | if (vp->v_mount != mp) |
743 | goto loop; | |
f0556f86 KM |
744 | nvp = vp->v_mountf; |
745 | /* | |
746 | * Skip over a selected vnode. | |
f0556f86 KM |
747 | */ |
748 | if (vp == skipvp) | |
749 | continue; | |
36ef03ec KM |
750 | /* |
751 | * Skip over a vnodes marked VSYSTEM. | |
752 | */ | |
753 | if ((flags & SKIPSYSTEM) && (vp->v_flag & VSYSTEM)) | |
754 | continue; | |
f0556f86 | 755 | /* |
7f7b7d89 | 756 | * With v_usecount == 0, all we need to do is clear |
f0556f86 KM |
757 | * out the vnode data structures and we are done. |
758 | */ | |
7f7b7d89 | 759 | if (vp->v_usecount == 0) { |
f0556f86 KM |
760 | vgone(vp); |
761 | continue; | |
762 | } | |
763 | /* | |
764 | * For block or character devices, revert to an | |
765 | * anonymous device. For all other files, just kill them. | |
766 | */ | |
36ef03ec | 767 | if (flags & FORCECLOSE) { |
f0556f86 KM |
768 | if (vp->v_type != VBLK && vp->v_type != VCHR) { |
769 | vgone(vp); | |
770 | } else { | |
771 | vclean(vp, 0); | |
772 | vp->v_op = &spec_vnodeops; | |
773 | insmntque(vp, (struct mount *)0); | |
774 | } | |
775 | continue; | |
776 | } | |
777 | if (busyprt) | |
0bf84b18 | 778 | vprint("vflush: busy vnode", vp); |
f0556f86 KM |
779 | busy++; |
780 | } | |
781 | if (busy) | |
782 | return (EBUSY); | |
783 | return (0); | |
784 | } | |
785 | ||
ef24f6dd KM |
786 | /* |
787 | * Disassociate the underlying file system from a vnode. | |
ef24f6dd | 788 | */ |
36ef03ec | 789 | void vclean(vp, flags) |
ef24f6dd | 790 | register struct vnode *vp; |
aacc1bff | 791 | int flags; |
ef24f6dd KM |
792 | { |
793 | struct vnodeops *origops; | |
2bae1875 | 794 | int active; |
c099667a | 795 | struct proc *p = curproc; /* XXX */ |
ef24f6dd | 796 | |
2bae1875 KM |
797 | /* |
798 | * Check to see if the vnode is in use. | |
0bf84b18 KM |
799 | * If so we have to reference it before we clean it out |
800 | * so that its count cannot fall to zero and generate a | |
801 | * race against ourselves to recycle it. | |
2bae1875 | 802 | */ |
7f7b7d89 | 803 | if (active = vp->v_usecount) |
2bae1875 | 804 | VREF(vp); |
2bae1875 KM |
805 | /* |
806 | * Prevent the vnode from being recycled or | |
807 | * brought into use while we clean it out. | |
808 | */ | |
0bf84b18 KM |
809 | if (vp->v_flag & VXLOCK) |
810 | panic("vclean: deadlock"); | |
ef24f6dd | 811 | vp->v_flag |= VXLOCK; |
0bf84b18 KM |
812 | /* |
813 | * Even if the count is zero, the VOP_INACTIVE routine may still | |
814 | * have the object locked while it cleans it out. The VOP_LOCK | |
815 | * ensures that the VOP_INACTIVE routine is done with its work. | |
816 | * For active vnodes, it ensures that no other activity can | |
817 | * occur while the buffer list is being cleaned out. | |
818 | */ | |
819 | VOP_LOCK(vp); | |
36ef03ec | 820 | if (flags & DOCLOSE) |
0bf84b18 | 821 | vinvalbuf(vp, 1); |
ef24f6dd KM |
822 | /* |
823 | * Prevent any further operations on the vnode from | |
824 | * being passed through to the old file system. | |
825 | */ | |
826 | origops = vp->v_op; | |
827 | vp->v_op = &dead_vnodeops; | |
828 | vp->v_tag = VT_NON; | |
829 | /* | |
2bae1875 KM |
830 | * If purging an active vnode, it must be unlocked, closed, |
831 | * and deactivated before being reclaimed. | |
ef24f6dd | 832 | */ |
20454d5a | 833 | (*(origops->vop_unlock))(vp); |
2bae1875 | 834 | if (active) { |
36ef03ec | 835 | if (flags & DOCLOSE) |
20454d5a KM |
836 | (*(origops->vop_close))(vp, IO_NDELAY, NOCRED, p); |
837 | (*(origops->vop_inactive))(vp, p); | |
ef24f6dd KM |
838 | } |
839 | /* | |
840 | * Reclaim the vnode. | |
841 | */ | |
20454d5a | 842 | if ((*(origops->vop_reclaim))(vp)) |
ef24f6dd | 843 | panic("vclean: cannot reclaim"); |
2bae1875 KM |
844 | if (active) |
845 | vrele(vp); | |
ef24f6dd KM |
846 | /* |
847 | * Done with purge, notify sleepers in vget of the grim news. | |
848 | */ | |
849 | vp->v_flag &= ~VXLOCK; | |
850 | if (vp->v_flag & VXWANT) { | |
851 | vp->v_flag &= ~VXWANT; | |
852 | wakeup((caddr_t)vp); | |
853 | } | |
854 | } | |
855 | ||
ef62830d KM |
856 | /* |
857 | * Eliminate all activity associated with the requested vnode | |
858 | * and with all vnodes aliased to the requested vnode. | |
859 | */ | |
860 | void vgoneall(vp) | |
861 | register struct vnode *vp; | |
862 | { | |
7f7b7d89 | 863 | register struct vnode *vq; |
ef62830d | 864 | |
7a7b3a95 KM |
865 | if (vp->v_flag & VALIASED) { |
866 | /* | |
867 | * If a vgone (or vclean) is already in progress, | |
868 | * wait until it is done and return. | |
869 | */ | |
870 | if (vp->v_flag & VXLOCK) { | |
871 | vp->v_flag |= VXWANT; | |
872 | sleep((caddr_t)vp, PINOD); | |
873 | return; | |
874 | } | |
875 | /* | |
876 | * Ensure that vp will not be vgone'd while we | |
877 | * are eliminating its aliases. | |
878 | */ | |
879 | vp->v_flag |= VXLOCK; | |
880 | while (vp->v_flag & VALIASED) { | |
881 | for (vq = *vp->v_hashchain; vq; vq = vq->v_specnext) { | |
882 | if (vq->v_rdev != vp->v_rdev || | |
883 | vq->v_type != vp->v_type || vp == vq) | |
884 | continue; | |
885 | vgone(vq); | |
886 | break; | |
887 | } | |
ef62830d | 888 | } |
7a7b3a95 KM |
889 | /* |
890 | * Remove the lock so that vgone below will | |
891 | * really eliminate the vnode after which time | |
892 | * vgone will awaken any sleepers. | |
893 | */ | |
894 | vp->v_flag &= ~VXLOCK; | |
ef62830d KM |
895 | } |
896 | vgone(vp); | |
897 | } | |
898 | ||
ef24f6dd KM |
899 | /* |
900 | * Eliminate all activity associated with a vnode | |
901 | * in preparation for reuse. | |
902 | */ | |
903 | void vgone(vp) | |
904 | register struct vnode *vp; | |
905 | { | |
7f7b7d89 | 906 | register struct vnode *vq; |
c0de8792 KM |
907 | struct vnode *vx; |
908 | long count; | |
ef24f6dd | 909 | |
4f55e3ec KM |
910 | /* |
911 | * If a vgone (or vclean) is already in progress, | |
912 | * wait until it is done and return. | |
913 | */ | |
914 | if (vp->v_flag & VXLOCK) { | |
915 | vp->v_flag |= VXWANT; | |
916 | sleep((caddr_t)vp, PINOD); | |
917 | return; | |
918 | } | |
ef24f6dd KM |
919 | /* |
920 | * Clean out the filesystem specific data. | |
921 | */ | |
36ef03ec | 922 | vclean(vp, DOCLOSE); |
ef24f6dd KM |
923 | /* |
924 | * Delete from old mount point vnode list, if on one. | |
925 | */ | |
926 | if (vp->v_mountb) { | |
927 | if (vq = vp->v_mountf) | |
928 | vq->v_mountb = vp->v_mountb; | |
929 | *vp->v_mountb = vq; | |
930 | vp->v_mountf = NULL; | |
931 | vp->v_mountb = NULL; | |
932 | } | |
933 | /* | |
934 | * If special device, remove it from special device alias list. | |
935 | */ | |
936 | if (vp->v_type == VBLK || vp->v_type == VCHR) { | |
7f7b7d89 KM |
937 | if (*vp->v_hashchain == vp) { |
938 | *vp->v_hashchain = vp->v_specnext; | |
ef24f6dd | 939 | } else { |
7f7b7d89 | 940 | for (vq = *vp->v_hashchain; vq; vq = vq->v_specnext) { |
c0de8792 | 941 | if (vq->v_specnext != vp) |
ef24f6dd | 942 | continue; |
c0de8792 | 943 | vq->v_specnext = vp->v_specnext; |
ef24f6dd KM |
944 | break; |
945 | } | |
c0de8792 | 946 | if (vq == NULL) |
ef24f6dd KM |
947 | panic("missing bdev"); |
948 | } | |
c0de8792 | 949 | if (vp->v_flag & VALIASED) { |
7f7b7d89 KM |
950 | count = 0; |
951 | for (vq = *vp->v_hashchain; vq; vq = vq->v_specnext) { | |
de81e10c KM |
952 | if (vq->v_rdev != vp->v_rdev || |
953 | vq->v_type != vp->v_type) | |
c0de8792 KM |
954 | continue; |
955 | count++; | |
956 | vx = vq; | |
957 | } | |
958 | if (count == 0) | |
959 | panic("missing alias"); | |
960 | if (count == 1) | |
961 | vx->v_flag &= ~VALIASED; | |
962 | vp->v_flag &= ~VALIASED; | |
963 | } | |
964 | FREE(vp->v_specinfo, M_VNODE); | |
965 | vp->v_specinfo = NULL; | |
ef24f6dd KM |
966 | } |
967 | /* | |
968 | * If it is on the freelist, move it to the head of the list. | |
969 | */ | |
970 | if (vp->v_freeb) { | |
971 | if (vq = vp->v_freef) | |
972 | vq->v_freeb = vp->v_freeb; | |
973 | else | |
974 | vfreet = vp->v_freeb; | |
975 | *vp->v_freeb = vq; | |
976 | vp->v_freef = vfreeh; | |
977 | vp->v_freeb = &vfreeh; | |
978 | vfreeh->v_freeb = &vp->v_freef; | |
979 | vfreeh = vp; | |
980 | } | |
2bae1875 | 981 | vp->v_type = VBAD; |
36d09cb1 | 982 | } |
ef62830d | 983 | |
2bcd6066 KM |
984 | /* |
985 | * Lookup a vnode by device number. | |
986 | */ | |
987 | vfinddev(dev, type, vpp) | |
988 | dev_t dev; | |
989 | enum vtype type; | |
990 | struct vnode **vpp; | |
991 | { | |
992 | register struct vnode *vp; | |
993 | ||
994 | for (vp = speclisth[SPECHASH(dev)]; vp; vp = vp->v_specnext) { | |
995 | if (dev != vp->v_rdev || type != vp->v_type) | |
996 | continue; | |
997 | *vpp = vp; | |
998 | return (0); | |
999 | } | |
1000 | return (1); | |
1001 | } | |
1002 | ||
ef62830d KM |
1003 | /* |
1004 | * Calculate the total number of references to a special device. | |
1005 | */ | |
1006 | vcount(vp) | |
1007 | register struct vnode *vp; | |
1008 | { | |
7f7b7d89 | 1009 | register struct vnode *vq; |
ef62830d KM |
1010 | int count; |
1011 | ||
1012 | if ((vp->v_flag & VALIASED) == 0) | |
7f7b7d89 | 1013 | return (vp->v_usecount); |
ef62830d | 1014 | loop: |
7f7b7d89 | 1015 | for (count = 0, vq = *vp->v_hashchain; vq; vq = vq->v_specnext) { |
de81e10c | 1016 | if (vq->v_rdev != vp->v_rdev || vq->v_type != vp->v_type) |
ef62830d KM |
1017 | continue; |
1018 | /* | |
1019 | * Alias, but not in use, so flush it out. | |
1020 | */ | |
7f7b7d89 | 1021 | if (vq->v_usecount == 0) { |
ef62830d KM |
1022 | vgone(vq); |
1023 | goto loop; | |
1024 | } | |
7f7b7d89 | 1025 | count += vq->v_usecount; |
ef62830d KM |
1026 | } |
1027 | return (count); | |
1028 | } | |
0bf84b18 KM |
1029 | |
1030 | /* | |
1031 | * Print out a description of a vnode. | |
1032 | */ | |
1033 | static char *typename[] = | |
61f846a8 | 1034 | { "VNON", "VREG", "VDIR", "VBLK", "VCHR", "VLNK", "VSOCK", "VFIFO", "VBAD" }; |
0bf84b18 KM |
1035 | |
1036 | vprint(label, vp) | |
1037 | char *label; | |
1038 | register struct vnode *vp; | |
1039 | { | |
f2f730c6 | 1040 | char buf[64]; |
0bf84b18 KM |
1041 | |
1042 | if (label != NULL) | |
1043 | printf("%s: ", label); | |
f2f730c6 | 1044 | printf("type %s, usecount %d, refcount %d,", typename[vp->v_type], |
7f7b7d89 | 1045 | vp->v_usecount, vp->v_holdcnt); |
f2f730c6 KM |
1046 | buf[0] = '\0'; |
1047 | if (vp->v_flag & VROOT) | |
1048 | strcat(buf, "|VROOT"); | |
1049 | if (vp->v_flag & VTEXT) | |
1050 | strcat(buf, "|VTEXT"); | |
36ef03ec KM |
1051 | if (vp->v_flag & VSYSTEM) |
1052 | strcat(buf, "|VSYSTEM"); | |
36ef03ec KM |
1053 | if (vp->v_flag & VXLOCK) |
1054 | strcat(buf, "|VXLOCK"); | |
1055 | if (vp->v_flag & VXWANT) | |
1056 | strcat(buf, "|VXWANT"); | |
f2f730c6 KM |
1057 | if (vp->v_flag & VBWAIT) |
1058 | strcat(buf, "|VBWAIT"); | |
36ef03ec KM |
1059 | if (vp->v_flag & VALIASED) |
1060 | strcat(buf, "|VALIASED"); | |
f2f730c6 KM |
1061 | if (buf[0] != '\0') |
1062 | printf(" flags (%s)", &buf[1]); | |
1063 | printf("\n\t"); | |
0bf84b18 KM |
1064 | VOP_PRINT(vp); |
1065 | } | |
985cbdd5 | 1066 | |
34c62e18 KM |
1067 | #ifdef DEBUG |
1068 | /* | |
1069 | * List all of the locked vnodes in the system. | |
1070 | * Called when debugging the kernel. | |
1071 | */ | |
1072 | printlockedvnodes() | |
1073 | { | |
1074 | register struct mount *mp; | |
1075 | register struct vnode *vp; | |
1076 | ||
1077 | printf("Locked vnodes\n"); | |
1078 | mp = rootfs; | |
1079 | do { | |
1080 | for (vp = mp->mnt_mounth; vp; vp = vp->v_mountf) | |
1081 | if (VOP_ISLOCKED(vp)) | |
1082 | vprint((char *)0, vp); | |
1083 | mp = mp->mnt_next; | |
1084 | } while (mp != rootfs); | |
1085 | } | |
1086 | #endif | |
1087 | ||
985cbdd5 MT |
1088 | int kinfo_vdebug = 1; |
1089 | int kinfo_vgetfailed; | |
1090 | #define KINFO_VNODESLOP 10 | |
1091 | /* | |
1092 | * Dump vnode list (via kinfo). | |
1093 | * Copyout address of vnode followed by vnode. | |
1094 | */ | |
aacc1bff | 1095 | /* ARGSUSED */ |
985cbdd5 | 1096 | kinfo_vnode(op, where, acopysize, arg, aneeded) |
aacc1bff | 1097 | int op; |
985cbdd5 | 1098 | char *where; |
aacc1bff | 1099 | int *acopysize, arg, *aneeded; |
985cbdd5 MT |
1100 | { |
1101 | register struct mount *mp = rootfs; | |
36ef03ec | 1102 | struct mount *omp; |
985cbdd5 | 1103 | struct vnode *vp; |
985cbdd5 MT |
1104 | register char *bp = where, *savebp; |
1105 | char *ewhere = where + *acopysize; | |
1106 | int error; | |
1107 | ||
1108 | #define VPTRSZ sizeof (struct vnode *) | |
1109 | #define VNODESZ sizeof (struct vnode) | |
1110 | if (where == NULL) { | |
1111 | *aneeded = (numvnodes + KINFO_VNODESLOP) * (VPTRSZ + VNODESZ); | |
1112 | return (0); | |
1113 | } | |
1114 | ||
985cbdd5 | 1115 | do { |
36ef03ec | 1116 | if (vfs_busy(mp)) { |
54fb9dc2 | 1117 | mp = mp->mnt_next; |
36ef03ec KM |
1118 | continue; |
1119 | } | |
985cbdd5 MT |
1120 | savebp = bp; |
1121 | again: | |
4597dd33 | 1122 | for (vp = mp->mnt_mounth; vp; vp = vp->v_mountf) { |
41185b3b KM |
1123 | /* |
1124 | * Check that the vp is still associated with | |
1125 | * this filesystem. RACE: could have been | |
1126 | * recycled onto the same filesystem. | |
1127 | */ | |
4597dd33 KM |
1128 | if (vp->v_mount != mp) { |
1129 | if (kinfo_vdebug) | |
1130 | printf("kinfo: vp changed\n"); | |
1131 | bp = savebp; | |
1132 | goto again; | |
1133 | } | |
985cbdd5 MT |
1134 | if ((bp + VPTRSZ + VNODESZ <= ewhere) && |
1135 | ((error = copyout((caddr_t)&vp, bp, VPTRSZ)) || | |
1136 | (error = copyout((caddr_t)vp, bp + VPTRSZ, | |
41185b3b | 1137 | VNODESZ)))) |
985cbdd5 | 1138 | return (error); |
985cbdd5 | 1139 | bp += VPTRSZ + VNODESZ; |
985cbdd5 | 1140 | } |
36ef03ec | 1141 | omp = mp; |
54fb9dc2 | 1142 | mp = mp->mnt_next; |
36ef03ec | 1143 | vfs_unbusy(omp); |
985cbdd5 MT |
1144 | } while (mp != rootfs); |
1145 | ||
1146 | *aneeded = bp - where; | |
1147 | if (bp > ewhere) | |
1148 | *acopysize = ewhere - where; | |
1149 | else | |
1150 | *acopysize = bp - where; | |
1151 | return (0); | |
1152 | } |