kernfs_vnops.c revision 1.63.4.1 1 /* $NetBSD: kernfs_vnops.c,v 1.63.4.1 1999/08/02 22:27:51 thorpej Exp $ */
2
3 /*
4 * Copyright (c) 1992, 1993
5 * The Regents of the University of California. All rights reserved.
6 *
7 * This code is derived from software donated to Berkeley by
8 * Jan-Simon Pendry.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 * 3. All advertising materials mentioning features or use of this software
19 * must display the following acknowledgement:
20 * This product includes software developed by the University of
21 * California, Berkeley and its contributors.
22 * 4. Neither the name of the University nor the names of its contributors
23 * may be used to endorse or promote products derived from this software
24 * without specific prior written permission.
25 *
26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36 * SUCH DAMAGE.
37 *
38 * @(#)kernfs_vnops.c 8.15 (Berkeley) 5/21/95
39 */
40
41 /*
42 * Kernel parameter filesystem (/kern)
43 */
44
45 #include <sys/param.h>
46 #include <sys/systm.h>
47 #include <sys/kernel.h>
48 #include <sys/vmmeter.h>
49 #include <sys/types.h>
50 #include <sys/time.h>
51 #include <sys/proc.h>
52 #include <sys/vnode.h>
53 #include <sys/malloc.h>
54 #include <sys/file.h>
55 #include <sys/stat.h>
56 #include <sys/mount.h>
57 #include <sys/namei.h>
58 #include <sys/buf.h>
59 #include <sys/dirent.h>
60 #include <sys/msgbuf.h>
61
62 #include <miscfs/genfs/genfs.h>
63 #include <miscfs/kernfs/kernfs.h>
64
65 #include <vm/vm.h>
66
67 #include <uvm/uvm_extern.h>
68
69 #define KSTRING 256 /* Largest I/O available via this filesystem */
70 #define UIO_MX 32
71
72 #define READ_MODE (S_IRUSR|S_IRGRP|S_IROTH)
73 #define WRITE_MODE (S_IWUSR|S_IRUSR|S_IRGRP|S_IROTH)
74 #define DIR_MODE (S_IRUSR|S_IXUSR|S_IRGRP|S_IXGRP|S_IROTH|S_IXOTH)
75
76 struct kern_target kern_targets[] = {
77 /* NOTE: The name must be less than UIO_MX-16 chars in length */
78 #define N(s) sizeof(s)-1, s
79 /* name data tag type ro/rw */
80 { DT_DIR, N("."), 0, KTT_NULL, VDIR, DIR_MODE },
81 { DT_DIR, N(".."), 0, KTT_NULL, VDIR, DIR_MODE },
82 { DT_REG, N("boottime"), &boottime.tv_sec, KTT_INT, VREG, READ_MODE },
83 { DT_REG, N("copyright"), copyright, KTT_STRING, VREG, READ_MODE },
84 { DT_REG, N("hostname"), 0, KTT_HOSTNAME, VREG, WRITE_MODE },
85 { DT_REG, N("hz"), &hz, KTT_INT, VREG, READ_MODE },
86 { DT_REG, N("loadavg"), 0, KTT_AVENRUN, VREG, READ_MODE },
87 { DT_REG, N("msgbuf"), 0, KTT_MSGBUF, VREG, READ_MODE },
88 { DT_REG, N("pagesize"), &uvmexp.pagesize, KTT_INT, VREG, READ_MODE },
89 { DT_REG, N("physmem"), &physmem, KTT_INT, VREG, READ_MODE },
90 #if 0
91 { DT_DIR, N("root"), 0, KTT_NULL, VDIR, DIR_MODE },
92 #endif
93 { DT_BLK, N("rootdev"), &rootdev, KTT_DEVICE, VBLK, READ_MODE },
94 { DT_CHR, N("rrootdev"), &rrootdev, KTT_DEVICE, VCHR, READ_MODE },
95 { DT_REG, N("time"), 0, KTT_TIME, VREG, READ_MODE },
96 { DT_REG, N("version"), version, KTT_STRING, VREG, READ_MODE },
97 #undef N
98 };
99 static int nkern_targets = sizeof(kern_targets) / sizeof(kern_targets[0]);
100
101 int kernfs_lookup __P((void *));
102 #define kernfs_create genfs_eopnotsupp_rele
103 #define kernfs_mknod genfs_eopnotsupp_rele
104 #define kernfs_open genfs_nullop
105 #define kernfs_close genfs_nullop
106 int kernfs_access __P((void *));
107 int kernfs_getattr __P((void *));
108 int kernfs_setattr __P((void *));
109 int kernfs_read __P((void *));
110 int kernfs_write __P((void *));
111 #define kernfs_ioctl genfs_enoioctl
112 #define kernfs_poll genfs_poll
113 #define kernfs_revoke genfs_revoke
114 #define kernfs_mmap genfs_eopnotsupp
115 #define kernfs_fsync genfs_nullop
116 #define kernfs_seek genfs_nullop
117 #define kernfs_remove genfs_eopnotsupp_rele
118 int kernfs_link __P((void *));
119 #define kernfs_rename genfs_eopnotsupp_rele
120 #define kernfs_mkdir genfs_eopnotsupp_rele
121 #define kernfs_rmdir genfs_eopnotsupp_rele
122 int kernfs_symlink __P((void *));
123 int kernfs_readdir __P((void *));
124 #define kernfs_readlink genfs_eopnotsupp
125 #define kernfs_abortop genfs_abortop
126 int kernfs_inactive __P((void *));
127 int kernfs_reclaim __P((void *));
128 #define kernfs_lock genfs_lock
129 #define kernfs_unlock genfs_unlock
130 #define kernfs_bmap genfs_badop
131 #define kernfs_strategy genfs_badop
132 int kernfs_print __P((void *));
133 #define kernfs_islocked genfs_islocked
134 int kernfs_pathconf __P((void *));
135 #define kernfs_advlock genfs_einval
136 #define kernfs_blkatoff genfs_eopnotsupp
137 #define kernfs_valloc genfs_eopnotsupp
138 #define kernfs_vfree genfs_nullop
139 #define kernfs_truncate genfs_eopnotsupp
140 #define kernfs_update genfs_nullop
141 #define kernfs_bwrite genfs_eopnotsupp
142
143 int kernfs_xread __P((struct kern_target *, int, char **, int));
144 int kernfs_xwrite __P((struct kern_target *, char *, int));
145
146 int (**kernfs_vnodeop_p) __P((void *));
147 struct vnodeopv_entry_desc kernfs_vnodeop_entries[] = {
148 { &vop_default_desc, vn_default_error },
149 { &vop_lookup_desc, kernfs_lookup }, /* lookup */
150 { &vop_create_desc, kernfs_create }, /* create */
151 { &vop_mknod_desc, kernfs_mknod }, /* mknod */
152 { &vop_open_desc, kernfs_open }, /* open */
153 { &vop_close_desc, kernfs_close }, /* close */
154 { &vop_access_desc, kernfs_access }, /* access */
155 { &vop_getattr_desc, kernfs_getattr }, /* getattr */
156 { &vop_setattr_desc, kernfs_setattr }, /* setattr */
157 { &vop_read_desc, kernfs_read }, /* read */
158 { &vop_write_desc, kernfs_write }, /* write */
159 { &vop_ioctl_desc, kernfs_ioctl }, /* ioctl */
160 { &vop_poll_desc, kernfs_poll }, /* poll */
161 { &vop_revoke_desc, kernfs_revoke }, /* revoke */
162 { &vop_mmap_desc, kernfs_mmap }, /* mmap */
163 { &vop_fsync_desc, kernfs_fsync }, /* fsync */
164 { &vop_seek_desc, kernfs_seek }, /* seek */
165 { &vop_remove_desc, kernfs_remove }, /* remove */
166 { &vop_link_desc, kernfs_link }, /* link */
167 { &vop_rename_desc, kernfs_rename }, /* rename */
168 { &vop_mkdir_desc, kernfs_mkdir }, /* mkdir */
169 { &vop_rmdir_desc, kernfs_rmdir }, /* rmdir */
170 { &vop_symlink_desc, kernfs_symlink }, /* symlink */
171 { &vop_readdir_desc, kernfs_readdir }, /* readdir */
172 { &vop_readlink_desc, kernfs_readlink }, /* readlink */
173 { &vop_abortop_desc, kernfs_abortop }, /* abortop */
174 { &vop_inactive_desc, kernfs_inactive }, /* inactive */
175 { &vop_reclaim_desc, kernfs_reclaim }, /* reclaim */
176 { &vop_lock_desc, kernfs_lock }, /* lock */
177 { &vop_unlock_desc, kernfs_unlock }, /* unlock */
178 { &vop_bmap_desc, kernfs_bmap }, /* bmap */
179 { &vop_strategy_desc, kernfs_strategy }, /* strategy */
180 { &vop_print_desc, kernfs_print }, /* print */
181 { &vop_islocked_desc, kernfs_islocked }, /* islocked */
182 { &vop_pathconf_desc, kernfs_pathconf }, /* pathconf */
183 { &vop_advlock_desc, kernfs_advlock }, /* advlock */
184 { &vop_blkatoff_desc, kernfs_blkatoff }, /* blkatoff */
185 { &vop_valloc_desc, kernfs_valloc }, /* valloc */
186 { &vop_vfree_desc, kernfs_vfree }, /* vfree */
187 { &vop_truncate_desc, kernfs_truncate }, /* truncate */
188 { &vop_update_desc, kernfs_update }, /* update */
189 { &vop_bwrite_desc, kernfs_bwrite }, /* bwrite */
190 { (struct vnodeop_desc*)NULL, (int(*) __P((void *)))NULL }
191 };
192 struct vnodeopv_desc kernfs_vnodeop_opv_desc =
193 { &kernfs_vnodeop_p, kernfs_vnodeop_entries };
194
195 int
196 kernfs_xread(kt, off, bufp, len)
197 struct kern_target *kt;
198 int off;
199 char **bufp;
200 int len;
201 {
202
203 switch (kt->kt_tag) {
204 case KTT_TIME: {
205 struct timeval tv;
206
207 microtime(&tv);
208 sprintf(*bufp, "%ld %ld\n", tv.tv_sec, tv.tv_usec);
209 break;
210 }
211
212 case KTT_INT: {
213 int *ip = kt->kt_data;
214
215 sprintf(*bufp, "%d\n", *ip);
216 break;
217 }
218
219 case KTT_STRING: {
220 char *cp = kt->kt_data;
221
222 *bufp = cp;
223 break;
224 }
225
226 case KTT_MSGBUF: {
227 long n;
228
229 /*
230 * deal with cases where the message buffer has
231 * become corrupted.
232 */
233 if (!msgbufenabled || msgbufp->msg_magic != MSG_MAGIC) {
234 msgbufenabled = 0;
235 return (ENXIO);
236 }
237
238 /*
239 * Note that reads of /kern/msgbuf won't necessarily yield
240 * consistent results, if the message buffer is modified
241 * while the read is in progress. The worst that can happen
242 * is that incorrect data will be read. There's no way
243 * that this can crash the system unless the values in the
244 * message buffer header are corrupted, but that'll cause
245 * the system to die anyway.
246 */
247 if (off >= msgbufp->msg_bufs)
248 return (0);
249 n = msgbufp->msg_bufx + off;
250 if (n >= msgbufp->msg_bufs)
251 n -= msgbufp->msg_bufs;
252 len = min(msgbufp->msg_bufs - n, msgbufp->msg_bufs - off);
253 *bufp = msgbufp->msg_bufc + n;
254 return (len);
255 }
256
257 case KTT_HOSTNAME: {
258 char *cp = hostname;
259 int xlen = hostnamelen;
260
261 if (xlen >= (len-2))
262 return (EINVAL);
263
264 memcpy(*bufp, cp, xlen);
265 (*bufp)[xlen] = '\n';
266 (*bufp)[xlen+1] = '\0';
267 break;
268 }
269
270 case KTT_AVENRUN:
271 averunnable.fscale = FSCALE;
272 sprintf(*bufp, "%d %d %d %ld\n",
273 averunnable.ldavg[0], averunnable.ldavg[1],
274 averunnable.ldavg[2], averunnable.fscale);
275 break;
276
277 default:
278 return (0);
279 }
280
281 len = strlen(*bufp);
282 if (len <= off)
283 return (0);
284 *bufp += off;
285 return (len - off);
286 }
287
288 int
289 kernfs_xwrite(kt, buf, len)
290 struct kern_target *kt;
291 char *buf;
292 int len;
293 {
294
295 switch (kt->kt_tag) {
296 case KTT_HOSTNAME:
297 if (buf[len-1] == '\n')
298 --len;
299 memcpy(hostname, buf, len);
300 hostname[len] = '\0';
301 hostnamelen = len;
302 return (0);
303
304 default:
305 return (EIO);
306 }
307 }
308
309
310 /*
311 * vp is the current namei directory
312 * ndp is the name to locate in that directory...
313 */
314 int
315 kernfs_lookup(v)
316 void *v;
317 {
318 struct vop_lookup_args /* {
319 struct vnode * a_dvp;
320 struct vnode ** a_vpp;
321 struct componentname * a_cnp;
322 } */ *ap = v;
323 struct componentname *cnp = ap->a_cnp;
324 struct vnode **vpp = ap->a_vpp;
325 struct vnode *dvp = ap->a_dvp;
326 const char *pname = cnp->cn_nameptr;
327 struct kern_target *kt;
328 struct vnode *fvp;
329 int error, i, wantpunlock;
330
331 #ifdef KERNFS_DIAGNOSTIC
332 printf("kernfs_lookup(%p)\n", ap);
333 printf("kernfs_lookup(dp = %p, vpp = %p, cnp = %p)\n", dvp, vpp, ap->a_cnp);
334 printf("kernfs_lookup(%s)\n", pname);
335 #endif
336
337 *vpp = NULLVP;
338 cnp->cn_flags &= ~PDIRUNLOCK;
339
340 if (cnp->cn_nameiop == DELETE || cnp->cn_nameiop == RENAME)
341 return (EROFS);
342
343 if (cnp->cn_namelen == 1 && *pname == '.') {
344 *vpp = dvp;
345 VREF(dvp);
346 return (0);
347 }
348
349 /*
350 * This code only supports a flat directory, so we don't
351 * need to worry about ..
352 */
353
354 #if 0
355 if (cnp->cn_namelen == 4 && memcmp(pname, "root", 4) == 0) {
356 *vpp = rootdir;
357 VREF(rootdir);
358 vn_lock(rootdir, LK_SHARED | LK_RETRY);
359 return (0);
360 }
361 #endif
362
363 wantpunlock = (~cnp->cn_flags & (LOCKPARENT | ISLASTCN));
364
365 for (kt = kern_targets, i = 0; i < nkern_targets; kt++, i++) {
366 if (cnp->cn_namelen == kt->kt_namlen &&
367 memcmp(kt->kt_name, pname, cnp->cn_namelen) == 0)
368 goto found;
369 }
370
371 #ifdef KERNFS_DIAGNOSTIC
372 printf("kernfs_lookup: i = %d, failed", i);
373 #endif
374
375 return (cnp->cn_nameiop == LOOKUP ? ENOENT : EROFS);
376
377 found:
378 if (kt->kt_tag == KTT_DEVICE) {
379 dev_t *dp = kt->kt_data;
380 loop:
381 if (*dp == NODEV || !vfinddev(*dp, kt->kt_vtype, &fvp)) {
382 return (ENOENT);
383 }
384 *vpp = fvp;
385 if (vget(fvp, LK_EXCLUSIVE))
386 goto loop;
387 if (wantpunlock) {
388 VOP_UNLOCK(dvp, 0);
389 cnp->cn_flags |= PDIRUNLOCK;
390 }
391 return (0);
392 }
393
394 #ifdef KERNFS_DIAGNOSTIC
395 printf("kernfs_lookup: allocate new vnode\n");
396 #endif
397 error = getnewvnode(VT_KERNFS, dvp->v_mount, kernfs_vnodeop_p, &fvp);
398 if (error) {
399 return (error);
400 }
401
402 MALLOC(fvp->v_data, void *, sizeof(struct kernfs_node), M_TEMP,
403 M_WAITOK);
404 VTOKERN(fvp)->kf_kt = kt;
405 fvp->v_type = kt->kt_vtype;
406 vn_lock(fvp, LK_EXCLUSIVE | LK_RETRY);
407 *vpp = fvp;
408
409 #ifdef KERNFS_DIAGNOSTIC
410 printf("kernfs_lookup: newvp = %p\n", fvp);
411 #endif
412 if (wantpunlock) {
413 VOP_UNLOCK(dvp, 0);
414 cnp->cn_flags |= PDIRUNLOCK;
415 }
416 return (0);
417 }
418
419 int
420 kernfs_access(v)
421 void *v;
422 {
423 struct vop_access_args /* {
424 struct vnode *a_vp;
425 int a_mode;
426 struct ucred *a_cred;
427 struct proc *a_p;
428 } */ *ap = v;
429 struct vnode *vp = ap->a_vp;
430 mode_t mode;
431
432 if (vp->v_flag & VROOT) {
433 mode = DIR_MODE;
434 } else {
435 struct kern_target *kt = VTOKERN(vp)->kf_kt;
436 mode = kt->kt_mode;
437 }
438
439 return (vaccess(vp->v_type, mode, (uid_t)0, (gid_t)0, ap->a_mode,
440 ap->a_cred));
441 }
442
443 int
444 kernfs_getattr(v)
445 void *v;
446 {
447 struct vop_getattr_args /* {
448 struct vnode *a_vp;
449 struct vattr *a_vap;
450 struct ucred *a_cred;
451 struct proc *a_p;
452 } */ *ap = v;
453 struct vnode *vp = ap->a_vp;
454 struct vattr *vap = ap->a_vap;
455 struct timeval tv;
456 int error = 0;
457 char strbuf[KSTRING], *buf;
458
459 memset((caddr_t) vap, 0, sizeof(*vap));
460 vattr_null(vap);
461 vap->va_uid = 0;
462 vap->va_gid = 0;
463 vap->va_fsid = vp->v_mount->mnt_stat.f_fsid.val[0];
464 vap->va_size = 0;
465 vap->va_blocksize = DEV_BSIZE;
466 microtime(&tv);
467 TIMEVAL_TO_TIMESPEC(&tv, &vap->va_atime);
468 vap->va_mtime = vap->va_atime;
469 vap->va_ctime = vap->va_ctime;
470 vap->va_gen = 0;
471 vap->va_flags = 0;
472 vap->va_rdev = 0;
473 vap->va_bytes = 0;
474
475 if (vp->v_flag & VROOT) {
476 #ifdef KERNFS_DIAGNOSTIC
477 printf("kernfs_getattr: stat rootdir\n");
478 #endif
479 vap->va_type = VDIR;
480 vap->va_mode = DIR_MODE;
481 vap->va_nlink = 2;
482 vap->va_fileid = 2;
483 vap->va_size = DEV_BSIZE;
484 } else {
485 struct kern_target *kt = VTOKERN(vp)->kf_kt;
486 int nbytes, total;
487 #ifdef KERNFS_DIAGNOSTIC
488 printf("kernfs_getattr: stat target %s\n", kt->kt_name);
489 #endif
490 vap->va_type = kt->kt_vtype;
491 vap->va_mode = kt->kt_mode;
492 vap->va_nlink = 1;
493 vap->va_fileid = 1 + (kt - kern_targets);
494 total = 0;
495 while (buf = strbuf,
496 nbytes = kernfs_xread(kt, total, &buf, sizeof(strbuf)))
497 total += nbytes;
498 vap->va_size = total;
499 }
500
501 #ifdef KERNFS_DIAGNOSTIC
502 printf("kernfs_getattr: return error %d\n", error);
503 #endif
504 return (error);
505 }
506
507 /*ARGSUSED*/
508 int
509 kernfs_setattr(v)
510 void *v;
511 {
512 /*
513 * Silently ignore attribute changes.
514 * This allows for open with truncate to have no
515 * effect until some data is written. I want to
516 * do it this way because all writes are atomic.
517 */
518 return (0);
519 }
520
521 int
522 kernfs_read(v)
523 void *v;
524 {
525 struct vop_read_args /* {
526 struct vnode *a_vp;
527 struct uio *a_uio;
528 int a_ioflag;
529 struct ucred *a_cred;
530 } */ *ap = v;
531 struct vnode *vp = ap->a_vp;
532 struct uio *uio = ap->a_uio;
533 struct kern_target *kt;
534 char strbuf[KSTRING], *buf;
535 int off, len;
536 int error;
537
538 if (vp->v_type == VDIR)
539 return (EOPNOTSUPP);
540
541 kt = VTOKERN(vp)->kf_kt;
542
543 #ifdef KERNFS_DIAGNOSTIC
544 printf("kern_read %s\n", kt->kt_name);
545 #endif
546
547 off = uio->uio_offset;
548 #if 0
549 while (buf = strbuf,
550 #else
551 if (buf = strbuf,
552 #endif
553 len = kernfs_xread(kt, off, &buf, sizeof(strbuf))) {
554 if ((error = uiomove(buf, len, uio)) != 0)
555 return (error);
556 off += len;
557 }
558 return (0);
559 }
560
561 int
562 kernfs_write(v)
563 void *v;
564 {
565 struct vop_write_args /* {
566 struct vnode *a_vp;
567 struct uio *a_uio;
568 int a_ioflag;
569 struct ucred *a_cred;
570 } */ *ap = v;
571 struct vnode *vp = ap->a_vp;
572 struct uio *uio = ap->a_uio;
573 struct kern_target *kt;
574 int error, xlen;
575 char strbuf[KSTRING];
576
577 if (vp->v_type == VDIR)
578 return (EOPNOTSUPP);
579
580 kt = VTOKERN(vp)->kf_kt;
581
582 if (uio->uio_offset != 0)
583 return (EINVAL);
584
585 xlen = min(uio->uio_resid, KSTRING-1);
586 if ((error = uiomove(strbuf, xlen, uio)) != 0)
587 return (error);
588
589 if (uio->uio_resid != 0)
590 return (EIO);
591
592 strbuf[xlen] = '\0';
593 xlen = strlen(strbuf);
594 return (kernfs_xwrite(kt, strbuf, xlen));
595 }
596
597 int
598 kernfs_readdir(v)
599 void *v;
600 {
601 struct vop_readdir_args /* {
602 struct vnode *a_vp;
603 struct uio *a_uio;
604 struct ucred *a_cred;
605 int *a_eofflag;
606 off_t **a_cookies;
607 int a_*ncookies;
608 } */ *ap = v;
609 struct uio *uio = ap->a_uio;
610 struct dirent d;
611 struct kern_target *kt;
612 int i;
613 int error;
614 off_t *cookies = NULL;
615 int ncookies = 0, nc = 0;
616
617 if (ap->a_vp->v_type != VDIR)
618 return (ENOTDIR);
619
620 if (uio->uio_resid < UIO_MX)
621 return (EINVAL);
622 if (uio->uio_offset < 0)
623 return (EINVAL);
624
625 error = 0;
626 i = uio->uio_offset;
627 memset((caddr_t)&d, 0, UIO_MX);
628 d.d_reclen = UIO_MX;
629
630 if (ap->a_ncookies) {
631 nc = uio->uio_resid / UIO_MX;
632 nc = min(nc, (nkern_targets - i));
633 MALLOC(cookies, off_t *, nc * sizeof(off_t), M_TEMP,
634 M_WAITOK);
635 *ap->a_cookies = cookies;
636 }
637
638 for (kt = &kern_targets[i];
639 uio->uio_resid >= UIO_MX && i < nkern_targets; kt++, i++) {
640 #ifdef KERNFS_DIAGNOSTIC
641 printf("kernfs_readdir: i = %d\n", i);
642 #endif
643
644 if (kt->kt_tag == KTT_DEVICE) {
645 dev_t *dp = kt->kt_data;
646 struct vnode *fvp;
647
648 if (*dp == NODEV || !vfinddev(*dp, kt->kt_vtype, &fvp))
649 continue;
650 }
651
652 d.d_fileno = i + 3;
653 d.d_namlen = kt->kt_namlen;
654 memcpy(d.d_name, kt->kt_name, kt->kt_namlen + 1);
655 d.d_type = kt->kt_type;
656
657 if ((error = uiomove((caddr_t)&d, UIO_MX, uio)) != 0)
658 break;
659 if (cookies) {
660 *cookies++ = i + 1;
661 ncookies++;
662 }
663 }
664
665 if (ap->a_ncookies) {
666 if (error) {
667 FREE(*ap->a_cookies, M_TEMP);
668 *ap->a_ncookies = 0;
669 *ap->a_cookies = NULL;
670 } else
671 *ap->a_ncookies = ncookies;
672 }
673
674 uio->uio_offset = i;
675 return (error);
676 }
677
678 int
679 kernfs_inactive(v)
680 void *v;
681 {
682 struct vop_inactive_args /* {
683 struct vnode *a_vp;
684 struct proc *a_p;
685 } */ *ap = v;
686 struct vnode *vp = ap->a_vp;
687
688 #ifdef KERNFS_DIAGNOSTIC
689 printf("kernfs_inactive(%p)\n", vp);
690 #endif
691 /*
692 * Clear out the v_type field to avoid
693 * nasty things happening in vgone().
694 */
695 VOP_UNLOCK(vp, 0);
696 vp->v_type = VNON;
697 return (0);
698 }
699
700 int
701 kernfs_reclaim(v)
702 void *v;
703 {
704 struct vop_reclaim_args /* {
705 struct vnode *a_vp;
706 } */ *ap = v;
707 struct vnode *vp = ap->a_vp;
708
709 #ifdef KERNFS_DIAGNOSTIC
710 printf("kernfs_reclaim(%p)\n", vp);
711 #endif
712 if (vp->v_data) {
713 FREE(vp->v_data, M_TEMP);
714 vp->v_data = 0;
715 }
716 return (0);
717 }
718
719 /*
720 * Return POSIX pathconf information applicable to special devices.
721 */
722 int
723 kernfs_pathconf(v)
724 void *v;
725 {
726 struct vop_pathconf_args /* {
727 struct vnode *a_vp;
728 int a_name;
729 register_t *a_retval;
730 } */ *ap = v;
731
732 switch (ap->a_name) {
733 case _PC_LINK_MAX:
734 *ap->a_retval = LINK_MAX;
735 return (0);
736 case _PC_MAX_CANON:
737 *ap->a_retval = MAX_CANON;
738 return (0);
739 case _PC_MAX_INPUT:
740 *ap->a_retval = MAX_INPUT;
741 return (0);
742 case _PC_PIPE_BUF:
743 *ap->a_retval = PIPE_BUF;
744 return (0);
745 case _PC_CHOWN_RESTRICTED:
746 *ap->a_retval = 1;
747 return (0);
748 case _PC_VDISABLE:
749 *ap->a_retval = _POSIX_VDISABLE;
750 return (0);
751 case _PC_SYNC_IO:
752 *ap->a_retval = 1;
753 return (0);
754 default:
755 return (EINVAL);
756 }
757 /* NOTREACHED */
758 }
759
760 /*
761 * Print out the contents of a /dev/fd vnode.
762 */
763 /* ARGSUSED */
764 int
765 kernfs_print(v)
766 void *v;
767 {
768
769 printf("tag VT_KERNFS, kernfs vnode\n");
770 return (0);
771 }
772
773 int
774 kernfs_link(v)
775 void *v;
776 {
777 struct vop_link_args /* {
778 struct vnode *a_dvp;
779 struct vnode *a_vp;
780 struct componentname *a_cnp;
781 } */ *ap = v;
782
783 VOP_ABORTOP(ap->a_dvp, ap->a_cnp);
784 vput(ap->a_dvp);
785 return (EROFS);
786 }
787
788 int
789 kernfs_symlink(v)
790 void *v;
791 {
792 struct vop_symlink_args /* {
793 struct vnode *a_dvp;
794 struct vnode **a_vpp;
795 struct componentname *a_cnp;
796 struct vattr *a_vap;
797 char *a_target;
798 } */ *ap = v;
799
800 VOP_ABORTOP(ap->a_dvp, ap->a_cnp);
801 vput(ap->a_dvp);
802 return (EROFS);
803 }
804