1 /*
2 * Copyright (c) 1989, 1993
3 * The Regents of the University of California. All rights reserved.
4 *
5 * This code is derived from software contributed
6 * to Berkeley by John Heidemann of the UCLA Ficus project.
7 *
8 * Source: * @(#)i405_init.c 2.10 92/04/27 UCLA Ficus project
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 * 3. All advertising materials mentioning features or use of this software
19 * must display the following acknowledgement:
20 * This product includes software developed by the University of
21 * California, Berkeley and its contributors.
22 * 4. Neither the name of the University nor the names of its contributors
23 * may be used to endorse or promote products derived from this software
24 * without specific prior written permission.
25 *
26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36 * SUCH DAMAGE.
37 *
38 */
39
40 #include <sys/param.h>
41 #include <sys/systm.h>
42 #include <sys/kernel.h>
43 #include <sys/lock.h>
44 #include <sys/malloc.h>
45 #include <sys/unistd.h>
46 #include <sys/vnode.h>
47 #include <sys/poll.h>
48
49 static int vop_nostrategy __P((struct vop_strategy_args *));
50
51 /*
52 * This vnode table stores what we want to do if the filesystem doesn't
53 * implement a particular VOP.
54 *
55 * If there is no specific entry here, we will return EOPNOTSUPP.
56 *
57 */
58
59 vop_t **default_vnodeop_p;
60 static struct vnodeopv_entry_desc default_vnodeop_entries[] = {
61 { &vop_default_desc, (vop_t *) vop_eopnotsupp },
62 { &vop_abortop_desc, (vop_t *) vop_null },
63 { &vop_advlock_desc, (vop_t *) vop_einval },
64 { &vop_bwrite_desc, (vop_t *) vop_stdbwrite },
65 { &vop_close_desc, (vop_t *) vop_null },
66 { &vop_fsync_desc, (vop_t *) vop_null },
67 { &vop_ioctl_desc, (vop_t *) vop_enotty },
68 { &vop_islocked_desc, (vop_t *) vop_noislocked },
69 { &vop_lease_desc, (vop_t *) vop_null },
70 { &vop_lock_desc, (vop_t *) vop_nolock },
71 { &vop_mmap_desc, (vop_t *) vop_einval },
72 { &vop_open_desc, (vop_t *) vop_null },
73 { &vop_pathconf_desc, (vop_t *) vop_einval },
74 { &vop_poll_desc, (vop_t *) vop_nopoll },
75 { &vop_readlink_desc, (vop_t *) vop_einval },
76 { &vop_reallocblks_desc, (vop_t *) vop_eopnotsupp },
77 { &vop_revoke_desc, (vop_t *) vop_revoke },
78 { &vop_strategy_desc, (vop_t *) vop_nostrategy },
79 { &vop_unlock_desc, (vop_t *) vop_nounlock },
80 { NULL, NULL }
81 };
82
83 static struct vnodeopv_desc default_vnodeop_opv_desc =
84 { &default_vnodeop_p, default_vnodeop_entries };
85
86 VNODEOP_SET(default_vnodeop_opv_desc);
87
88 int
89 vop_eopnotsupp(struct vop_generic_args *ap)
90 {
91 /*
92 printf("vop_notsupp[%s]\n", ap->a_desc->vdesc_name);
93 */
94
95 return (EOPNOTSUPP);
96 }
97
98 int
99 vop_ebadf(struct vop_generic_args *ap)
100 {
101
102 return (EBADF);
103 }
104
105 int
106 vop_enotty(struct vop_generic_args *ap)
107 {
108
109 return (ENOTTY);
110 }
111
112 int
113 vop_einval(struct vop_generic_args *ap)
114 {
115
116 return (EINVAL);
117 }
118
119 int
120 vop_null(struct vop_generic_args *ap)
121 {
122
123 return (0);
124 }
125
126 int
127 vop_defaultop(struct vop_generic_args *ap)
128 {
129
130 return (VOCALL(default_vnodeop_p, ap->a_desc->vdesc_offset, ap));
131 }
132
133 int
134 vop_panic(struct vop_generic_args *ap)
135 {
136
137 panic("illegal vnode op called");
138 }
139
140 static int
141 vop_nostrategy (struct vop_strategy_args *ap)
142 {
143 printf("No strategy for buffer at %p\n", ap->a_bp);
144 vprint("", ap->a_vp);
145 vprint("", ap->a_bp->b_vp);
146 ap->a_bp->b_flags |= B_ERROR;
147 ap->a_bp->b_error = EOPNOTSUPP;
148 biodone(ap->a_bp);
149 return (EOPNOTSUPP);
150 }
151
152 int
153 vop_stdpathconf(ap)
154 struct vop_pathconf_args /* {
155 struct vnode *a_vp;
156 int a_name;
157 int *a_retval;
158 } */ *ap;
159 {
160
161 switch (ap->a_name) {
162 case _PC_LINK_MAX:
163 *ap->a_retval = LINK_MAX;
164 return (0);
165 case _PC_MAX_CANON:
166 *ap->a_retval = MAX_CANON;
167 return (0);
168 case _PC_MAX_INPUT:
169 *ap->a_retval = MAX_INPUT;
170 return (0);
171 case _PC_PIPE_BUF:
172 *ap->a_retval = PIPE_BUF;
173 return (0);
174 case _PC_CHOWN_RESTRICTED:
175 *ap->a_retval = 1;
176 return (0);
177 case _PC_VDISABLE:
178 *ap->a_retval = _POSIX_VDISABLE;
179 return (0);
180 default:
181 return (EINVAL);
182 }
183 /* NOTREACHED */
184 }
185
186 /*
187 * Standard lock, unlock and islocked functions.
188 *
189 * These depend on the lock structure being the first element in the
190 * inode, ie: vp->v_data points to the the lock!
191 */
192 int
193 vop_stdlock(ap)
194 struct vop_lock_args /* {
195 struct vnode *a_vp;
196 int a_flags;
197 struct proc *a_p;
198 } */ *ap;
199 {
200 struct lock *l;
201
202 if ((l = (struct lock *)ap->a_vp->v_data) == NULL) {
203 if (ap->a_flags & LK_INTERLOCK)
204 simple_unlock(&ap->a_vp->v_interlock);
205 return 0;
206 }
207
208 #ifndef DEBUG_LOCKS
209 return (lockmgr(l, ap->a_flags, &ap->a_vp->v_interlock, ap->a_p));
210 #else
211 return (debuglockmgr(l, ap->a_flags, &ap->a_vp->v_interlock, ap->a_p,
212 "vop_stdlock", ap->a_vp->filename, ap->a_vp->line));
213 #endif
214 }
215
216 int
217 vop_stdunlock(ap)
218 struct vop_unlock_args /* {
219 struct vnode *a_vp;
220 int a_flags;
221 struct proc *a_p;
222 } */ *ap;
223 {
224 struct lock *l;
225
226 if ((l = (struct lock *)ap->a_vp->v_data) == NULL) {
227 if (ap->a_flags & LK_INTERLOCK)
228 simple_unlock(&ap->a_vp->v_interlock);
229 return 0;
230 }
231
232 return (lockmgr(l, ap->a_flags | LK_RELEASE, &ap->a_vp->v_interlock,
233 ap->a_p));
234 }
235
236 int
237 vop_stdislocked(ap)
238 struct vop_islocked_args /* {
239 struct vnode *a_vp;
240 } */ *ap;
241 {
242 struct lock *l;
243
244 if ((l = (struct lock *)ap->a_vp->v_data) == NULL)
245 return 0;
246
247 return (lockstatus(l));
248 }
249
250 /*
251 * Return true for select/poll.
252 */
253 int
254 vop_nopoll(ap)
255 struct vop_poll_args /* {
256 struct vnode *a_vp;
257 int a_events;
258 struct ucred *a_cred;
259 struct proc *a_p;
260 } */ *ap;
261 {
262 /*
263 * Return true for read/write. If the user asked for something
264 * special, return POLLNVAL, so that clients have a way of
265 * determining reliably whether or not the extended
266 * functionality is present without hard-coding knowledge
267 * of specific filesystem implementations.
268 */
269 if (ap->a_events & ~POLLSTANDARD)
270 return (POLLNVAL);
271
272 return (ap->a_events & (POLLIN | POLLOUT | POLLRDNORM | POLLWRNORM));
273 }
274
275 /*
276 * Implement poll for local filesystems that support it.
277 */
278 int
279 vop_stdpoll(ap)
280 struct vop_poll_args /* {
281 struct vnode *a_vp;
282 int a_events;
283 struct ucred *a_cred;
284 struct proc *a_p;
285 } */ *ap;
286 {
287 if ((ap->a_events & ~POLLSTANDARD) == 0)
288 return (ap->a_events & (POLLRDNORM|POLLWRNORM));
289 return (vn_pollrecord(ap->a_vp, ap->a_p, ap->a_events));
290 }
291
292 int
293 vop_stdbwrite(ap)
294 struct vop_bwrite_args *ap;
295 {
296 return (bwrite(ap->a_bp));
297 }
298
299 /*
300 * Stubs to use when there is no locking to be done on the underlying object.
301 * A minimal shared lock is necessary to ensure that the underlying object
302 * is not revoked while an operation is in progress. So, an active shared
303 * count is maintained in an auxillary vnode lock structure.
304 */
305 int
306 vop_sharedlock(ap)
307 struct vop_lock_args /* {
308 struct vnode *a_vp;
309 int a_flags;
310 struct proc *a_p;
311 } */ *ap;
312 {
313 /*
314 * This code cannot be used until all the non-locking filesystems
315 * (notably NFS) are converted to properly lock and release nodes.
316 * Also, certain vnode operations change the locking state within
317 * the operation (create, mknod, remove, link, rename, mkdir, rmdir,
318 * and symlink). Ideally these operations should not change the
319 * lock state, but should be changed to let the caller of the
320 * function unlock them. Otherwise all intermediate vnode layers
321 * (such as union, umapfs, etc) must catch these functions to do
322 * the necessary locking at their layer. Note that the inactive
323 * and lookup operations also change their lock state, but this
324 * cannot be avoided, so these two operations will always need
325 * to be handled in intermediate layers.
326 */
327 struct vnode *vp = ap->a_vp;
328 int vnflags, flags = ap->a_flags;
329
330 if (vp->v_vnlock == NULL) {
331 if ((flags & LK_TYPE_MASK) == LK_DRAIN)
332 return (0);
333 MALLOC(vp->v_vnlock, struct lock *, sizeof(struct lock),
334 M_VNODE, M_WAITOK);
335 lockinit(vp->v_vnlock, PVFS, "vnlock", 0, LK_NOPAUSE);
336 }
337 switch (flags & LK_TYPE_MASK) {
338 case LK_DRAIN:
339 vnflags = LK_DRAIN;
340 break;
341 case LK_EXCLUSIVE:
342 #ifdef DEBUG_VFS_LOCKS
343 /*
344 * Normally, we use shared locks here, but that confuses
345 * the locking assertions.
346 */
347 vnflags = LK_EXCLUSIVE;
348 break;
349 #endif
350 case LK_SHARED:
351 vnflags = LK_SHARED;
352 break;
353 case LK_UPGRADE:
354 case LK_EXCLUPGRADE:
355 case LK_DOWNGRADE:
356 return (0);
357 case LK_RELEASE:
358 default:
359 panic("vop_sharedlock: bad operation %d", flags & LK_TYPE_MASK);
360 }
361 if (flags & LK_INTERLOCK)
362 vnflags |= LK_INTERLOCK;
363 #ifndef DEBUG_LOCKS
364 return (lockmgr(vp->v_vnlock, vnflags, &vp->v_interlock, ap->a_p));
365 #else
366 return (debuglockmgr(vp->v_vnlock, vnflags, &vp->v_interlock, ap->a_p,
367 "vop_sharedlock", vp->filename, vp->line));
368 #endif
369 }
370
371 /*
372 * Stubs to use when there is no locking to be done on the underlying object.
373 * A minimal shared lock is necessary to ensure that the underlying object
374 * is not revoked while an operation is in progress. So, an active shared
375 * count is maintained in an auxillary vnode lock structure.
376 */
377 int
378 vop_nolock(ap)
379 struct vop_lock_args /* {
380 struct vnode *a_vp;
381 int a_flags;
382 struct proc *a_p;
383 } */ *ap;
384 {
385 #ifdef notyet
386 /*
387 * This code cannot be used until all the non-locking filesystems
388 * (notably NFS) are converted to properly lock and release nodes.
389 * Also, certain vnode operations change the locking state within
390 * the operation (create, mknod, remove, link, rename, mkdir, rmdir,
391 * and symlink). Ideally these operations should not change the
392 * lock state, but should be changed to let the caller of the
393 * function unlock them. Otherwise all intermediate vnode layers
394 * (such as union, umapfs, etc) must catch these functions to do
395 * the necessary locking at their layer. Note that the inactive
396 * and lookup operations also change their lock state, but this
397 * cannot be avoided, so these two operations will always need
398 * to be handled in intermediate layers.
399 */
400 struct vnode *vp = ap->a_vp;
401 int vnflags, flags = ap->a_flags;
402
403 if (vp->v_vnlock == NULL) {
404 if ((flags & LK_TYPE_MASK) == LK_DRAIN)
405 return (0);
406 MALLOC(vp->v_vnlock, struct lock *, sizeof(struct lock),
407 M_VNODE, M_WAITOK);
408 lockinit(vp->v_vnlock, PVFS, "vnlock", 0, LK_NOPAUSE);
409 }
410 switch (flags & LK_TYPE_MASK) {
411 case LK_DRAIN:
412 vnflags = LK_DRAIN;
413 break;
414 case LK_EXCLUSIVE:
415 case LK_SHARED:
416 vnflags = LK_SHARED;
417 break;
418 case LK_UPGRADE:
419 case LK_EXCLUPGRADE:
420 case LK_DOWNGRADE:
421 return (0);
422 case LK_RELEASE:
423 default:
424 panic("vop_nolock: bad operation %d", flags & LK_TYPE_MASK);
425 }
426 if (flags & LK_INTERLOCK)
427 vnflags |= LK_INTERLOCK;
428 return(lockmgr(vp->v_vnlock, vnflags, &vp->v_interlock, ap->a_p));
429 #else /* for now */
430 /*
431 * Since we are not using the lock manager, we must clear
432 * the interlock here.
433 */
434 if (ap->a_flags & LK_INTERLOCK)
435 simple_unlock(&ap->a_vp->v_interlock);
436 return (0);
437 #endif
438 }
439
440 /*
441 * Do the inverse of vop_nolock, handling the interlock in a compatible way.
442 */
443 int
444 vop_nounlock(ap)
445 struct vop_unlock_args /* {
446 struct vnode *a_vp;
447 int a_flags;
448 struct proc *a_p;
449 } */ *ap;
450 {
451 struct vnode *vp = ap->a_vp;
452
453 if (vp->v_vnlock == NULL) {
454 if (ap->a_flags & LK_INTERLOCK)
455 simple_unlock(&ap->a_vp->v_interlock);
456 return (0);
457 }
458 return (lockmgr(vp->v_vnlock, LK_RELEASE | ap->a_flags,
459 &ap->a_vp->v_interlock, ap->a_p));
460 }
461
462 /*
463 * Return whether or not the node is in use.
464 */
465 int
466 vop_noislocked(ap)
467 struct vop_islocked_args /* {
468 struct vnode *a_vp;
469 } */ *ap;
470 {
471 struct vnode *vp = ap->a_vp;
472
473 if (vp->v_vnlock == NULL)
474 return (0);
475 return (lockstatus(vp->v_vnlock));
476 }
477
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