xref: /netbsd-src/sys/coda/coda_subr.c (revision 946379e7b37692fc43f68eb0d1c10daa0a7f3b6c)
1 /*	$NetBSD: coda_subr.c,v 1.31 2015/01/06 11:24:46 hannken Exp $	*/
2 
3 /*
4  *
5  *             Coda: an Experimental Distributed File System
6  *                              Release 3.1
7  *
8  *           Copyright (c) 1987-1998 Carnegie Mellon University
9  *                          All Rights Reserved
10  *
11  * Permission  to  use, copy, modify and distribute this software and its
12  * documentation is hereby granted,  provided  that  both  the  copyright
13  * notice  and  this  permission  notice  appear  in  all  copies  of the
14  * software, derivative works or  modified  versions,  and  any  portions
15  * thereof, and that both notices appear in supporting documentation, and
16  * that credit is given to Carnegie Mellon University  in  all  documents
17  * and publicity pertaining to direct or indirect use of this code or its
18  * derivatives.
19  *
20  * CODA IS AN EXPERIMENTAL SOFTWARE SYSTEM AND IS  KNOWN  TO  HAVE  BUGS,
21  * SOME  OF  WHICH MAY HAVE SERIOUS CONSEQUENCES.  CARNEGIE MELLON ALLOWS
22  * FREE USE OF THIS SOFTWARE IN ITS "AS IS" CONDITION.   CARNEGIE  MELLON
23  * DISCLAIMS  ANY  LIABILITY  OF  ANY  KIND  FOR  ANY  DAMAGES WHATSOEVER
24  * RESULTING DIRECTLY OR INDIRECTLY FROM THE USE OF THIS SOFTWARE  OR  OF
25  * ANY DERIVATIVE WORK.
26  *
27  * Carnegie  Mellon  encourages  users  of  this  software  to return any
28  * improvements or extensions that  they  make,  and  to  grant  Carnegie
29  * Mellon the rights to redistribute these changes without encumbrance.
30  *
31  * 	@(#) coda/coda_subr.c,v 1.1.1.1 1998/08/29 21:26:45 rvb Exp $
32  */
33 
34 /*
35  * Mach Operating System
36  * Copyright (c) 1989 Carnegie-Mellon University
37  * All rights reserved.  The CMU software License Agreement specifies
38  * the terms and conditions for use and redistribution.
39  */
40 
41 /*
42  * This code was written for the Coda file system at Carnegie Mellon
43  * University.  Contributers include David Steere, James Kistler, and
44  * M. Satyanarayanan.  */
45 
46 /* NOTES: rvb
47  * 1.	Added coda_unmounting to mark all cnodes as being UNMOUNTING.  This has to
48  *	 be done before dounmount is called.  Because some of the routines that
49  *	 dounmount calls before coda_unmounted might try to force flushes to venus.
50  *	 The vnode pager does this.
51  * 2.	coda_unmounting marks all cnodes scanning coda_cache.
52  * 3.	cfs_checkunmounting (under DEBUG) checks all cnodes by chasing the vnodes
53  *	 under the /coda mount point.
54  * 4.	coda_cacheprint (under DEBUG) prints names with vnode/cnode address
55  */
56 
57 #include <sys/cdefs.h>
58 __KERNEL_RCSID(0, "$NetBSD: coda_subr.c,v 1.31 2015/01/06 11:24:46 hannken Exp $");
59 
60 #include <sys/param.h>
61 #include <sys/systm.h>
62 #include <sys/malloc.h>
63 #include <sys/proc.h>
64 #include <sys/select.h>
65 #include <sys/mount.h>
66 #include <sys/kauth.h>
67 
68 #include <coda/coda.h>
69 #include <coda/cnode.h>
70 #include <coda/coda_subr.h>
71 #include <coda/coda_namecache.h>
72 
73 int codadebug = 0;
74 int coda_printf_delay = 0;  /* in microseconds */
75 int coda_vnop_print_entry = 0;
76 int coda_vfsop_print_entry = 0;
77 
78 #ifdef CODA_COMPAT_5
79 #define coda_hash(fid) \
80     (((fid)->Volume + (fid)->Vnode) & (CODA_CACHESIZE-1))
81 #define IS_DIR(cnode)        (cnode.Vnode & 0x1)
82 #else
83 #define coda_hash(fid) \
84     (coda_f2i(fid) & (CODA_CACHESIZE-1))
85 #define IS_DIR(cnode)        (cnode.opaque[2] & 0x1)
86 #endif
87 
88 struct vnode *coda_ctlvp;
89 
90 /*
91  * Lookup a cnode by fid. If the cnode is dying, it is bogus so skip it.
92  * The cnode is returned locked with the vnode referenced.
93  */
94 struct cnode *
95 coda_find(CodaFid *fid)
96 {
97 	int i;
98 	struct vnode *vp;
99 	struct cnode *cp;
100 
101 	for (i = 0; i < NVCODA; i++) {
102 		if (!coda_mnttbl[i].mi_started)
103 			continue;
104 		if (vcache_get(coda_mnttbl[i].mi_vfsp,
105 		    fid, sizeof(CodaFid), &vp) != 0)
106 			continue;
107 		mutex_enter(vp->v_interlock);
108 		cp = VTOC(vp);
109 		if (vp->v_type == VNON || cp == NULL || IS_UNMOUNTING(cp)) {
110 			mutex_exit(vp->v_interlock);
111 			vrele(vp);
112 			continue;
113 		}
114 		mutex_enter(&cp->c_lock);
115 		mutex_exit(vp->v_interlock);
116 
117 		return cp;
118 	}
119 
120 	return NULL;
121 }
122 
123 /*
124  * Iterate over all nodes attached to coda mounts.
125  */
126 static void
127 coda_iterate(bool (*f)(void *, struct vnode *), void *cl)
128 {
129 	int i;
130 	struct vnode_iterator *marker;
131 	struct vnode *vp;
132 
133 	for (i = 0; i < NVCODA; i++) {
134 		if (coda_mnttbl[i].mi_vfsp == NULL)
135 			continue;
136 		vfs_vnode_iterator_init(coda_mnttbl[i].mi_vfsp, &marker);
137 		while ((vp = vfs_vnode_iterator_next(marker, f, cl)) != NULL)
138 			vrele(vp);
139 		vfs_vnode_iterator_destroy(marker);
140 	}
141 }
142 
143 /*
144  * coda_kill is called as a side effect to vcopen. To prevent any
145  * cnodes left around from an earlier run of a venus or warden from
146  * causing problems with the new instance, mark any outstanding cnodes
147  * as dying. Future operations on these cnodes should fail (excepting
148  * coda_inactive of course!). Since multiple venii/wardens can be
149  * running, only kill the cnodes for a particular entry in the
150  * coda_mnttbl. -- DCS 12/1/94 */
151 
152 static bool
153 coda_kill_selector(void *cl, struct vnode *vp)
154 {
155 	int *count = cl;
156 
157 	(*count)++;
158 
159 	return false;
160 }
161 
162 int
163 coda_kill(struct mount *whoIam, enum dc_status dcstat)
164 {
165 	int count = 0;
166 	struct vnode_iterator *marker;
167 
168 	/*
169 	 * Algorithm is as follows:
170 	 *     Second, flush whatever vnodes we can from the name cache.
171 	 */
172 
173 	/* This is slightly overkill, but should work. Eventually it'd be
174 	 * nice to only flush those entries from the namecache that
175 	 * reference a vnode in this vfs.  */
176 	coda_nc_flush(dcstat);
177 
178 
179 	vfs_vnode_iterator_init(whoIam, &marker);
180 	vfs_vnode_iterator_next(marker, coda_kill_selector, &count);
181 	vfs_vnode_iterator_destroy(marker);
182 
183 	return count;
184 }
185 
186 /*
187  * There are two reasons why a cnode may be in use, it may be in the
188  * name cache or it may be executing.
189  */
190 static bool
191 coda_flush_selector(void *cl, struct vnode *vp)
192 {
193 	struct cnode *cp = VTOC(vp);
194 
195 	if (cp != NULL && !IS_DIR(cp->c_fid)) /* only files can be executed */
196 		coda_vmflush(cp);
197 
198 	return false;
199 }
200 void
201 coda_flush(enum dc_status dcstat)
202 {
203 
204     coda_clstat.ncalls++;
205     coda_clstat.reqs[CODA_FLUSH]++;
206 
207     coda_nc_flush(dcstat);	    /* flush files from the name cache */
208 
209     coda_iterate(coda_flush_selector, NULL);
210 }
211 
212 /*
213  * As a debugging measure, print out any cnodes that lived through a
214  * name cache flush.
215  */
216 static bool
217 coda_testflush_selector(void *cl, struct vnode *vp)
218 {
219 	struct cnode *cp = VTOC(vp);
220 
221 	if (cp != NULL)
222 		myprintf(("Live cnode fid %s count %d\n",
223 		     coda_f2s(&cp->c_fid), CTOV(cp)->v_usecount));
224 
225 	return false;
226 }
227 void
228 coda_testflush(void)
229 {
230 
231 	coda_iterate(coda_testflush_selector, NULL);
232 }
233 
234 /*
235  *     First, step through all cnodes and mark them unmounting.
236  *         NetBSD kernels may try to fsync them now that venus
237  *         is dead, which would be a bad thing.
238  *
239  */
240 static bool
241 coda_unmounting_selector(void *cl, struct vnode *vp)
242 {
243 	struct cnode *cp = VTOC(vp);
244 
245 	if (cp)
246 		cp->c_flags |= C_UNMOUNTING;
247 
248 	return false;
249 }
250 void
251 coda_unmounting(struct mount *whoIam)
252 {
253 	struct vnode_iterator *marker;
254 
255 	vfs_vnode_iterator_init(whoIam, &marker);
256 	vfs_vnode_iterator_next(marker, coda_unmounting_selector, NULL);
257 	vfs_vnode_iterator_destroy(marker);
258 }
259 
260 #ifdef	DEBUG
261 static bool
262 coda_checkunmounting_selector(void *cl, struct vnode *vp)
263 {
264 	struct cnode *cp = VTOC(vp);
265 
266 	if (cp && !(cp->c_flags & C_UNMOUNTING)) {
267 		printf("vp %p, cp %p missed\n", vp, cp);
268 		cp->c_flags |= C_UNMOUNTING;
269 	}
270 
271 	return false;
272 }
273 void
274 coda_checkunmounting(struct mount *mp)
275 {
276 	struct vnode_iterator *marker;
277 
278 	vfs_vnode_iterator_init(mp, &marker);
279 	vfs_vnode_iterator_next(marker, coda_checkunmounting_selector, NULL);
280 	vfs_vnode_iterator_destroy(marker);
281 }
282 
283 void
284 coda_cacheprint(struct mount *whoIam)
285 {
286 	struct vnode *vp;
287 	struct vnode_iterator *marker;
288 	int count = 0;
289 
290 	printf("coda_cacheprint: coda_ctlvp %p, cp %p", coda_ctlvp, VTOC(coda_ctlvp));
291 	coda_nc_name(VTOC(coda_ctlvp));
292 	printf("\n");
293 
294 	vfs_vnode_iterator_init(whoIam, &marker);
295 	while ((vp = vfs_vnode_iterator_next(marker, NULL, NULL)) != NULL) {
296 		printf("coda_cacheprint: vp %p, cp %p", vp, VTOC(vp));
297 		coda_nc_name(VTOC(vp));
298 		printf("\n");
299 		count++;
300 		vrele(vp);
301 	}
302 	printf("coda_cacheprint: count %d\n", count);
303 	vfs_vnode_iterator_destroy(marker);
304 }
305 #endif
306 
307 /*
308  * There are 6 cases where invalidations occur. The semantics of each
309  * is listed here.
310  *
311  * CODA_FLUSH     -- flush all entries from the name cache and the cnode cache.
312  * CODA_PURGEUSER -- flush all entries from the name cache for a specific user
313  *                  This call is a result of token expiration.
314  *
315  * The next two are the result of callbacks on a file or directory.
316  * CODA_ZAPDIR    -- flush the attributes for the dir from its cnode.
317  *                  Zap all children of this directory from the namecache.
318  * CODA_ZAPFILE   -- flush the attributes for a file.
319  *
320  * The fifth is a result of Venus detecting an inconsistent file.
321  * CODA_PURGEFID  -- flush the attribute for the file
322  *                  If it is a dir (odd vnode), purge its
323  *                  children from the namecache
324  *                  remove the file from the namecache.
325  *
326  * The sixth allows Venus to replace local fids with global ones
327  * during reintegration.
328  *
329  * CODA_REPLACE -- replace one CodaFid with another throughout the name cache
330  */
331 
332 int handleDownCall(int opcode, union outputArgs *out)
333 {
334     int error;
335 
336     /* Handle invalidate requests. */
337     switch (opcode) {
338       case CODA_FLUSH : {
339 
340 	  coda_flush(IS_DOWNCALL);
341 
342 	  CODADEBUG(CODA_FLUSH,coda_testflush();)    /* print remaining cnodes */
343 	      return(0);
344       }
345 
346       case CODA_PURGEUSER : {
347 	  coda_clstat.ncalls++;
348 	  coda_clstat.reqs[CODA_PURGEUSER]++;
349 
350 	  /* XXX - need to prevent fsync's */
351 #ifdef CODA_COMPAT_5
352 	  coda_nc_purge_user(out->coda_purgeuser.cred.cr_uid, IS_DOWNCALL);
353 #else
354 	  coda_nc_purge_user(out->coda_purgeuser.uid, IS_DOWNCALL);
355 #endif
356 	  return(0);
357       }
358 
359       case CODA_ZAPFILE : {
360 	  struct cnode *cp;
361 
362 	  error = 0;
363 	  coda_clstat.ncalls++;
364 	  coda_clstat.reqs[CODA_ZAPFILE]++;
365 
366 	  cp = coda_find(&out->coda_zapfile.Fid);
367 	  if (cp != NULL) {
368 	      cp->c_flags &= ~C_VATTR;
369 	      if (CTOV(cp)->v_iflag & VI_TEXT)
370 		  error = coda_vmflush(cp);
371 	      CODADEBUG(CODA_ZAPFILE, myprintf((
372 		    "zapfile: fid = %s, refcnt = %d, error = %d\n",
373 		    coda_f2s(&cp->c_fid), CTOV(cp)->v_usecount - 1, error)););
374 	      if (CTOV(cp)->v_usecount == 1) {
375 		  cp->c_flags |= C_PURGING;
376 	      }
377 	      mutex_exit(&cp->c_lock);
378 	      vrele(CTOV(cp));
379 	  }
380 
381 	  return(error);
382       }
383 
384       case CODA_ZAPDIR : {
385 	  struct cnode *cp;
386 
387 	  coda_clstat.ncalls++;
388 	  coda_clstat.reqs[CODA_ZAPDIR]++;
389 
390 	  cp = coda_find(&out->coda_zapdir.Fid);
391 	  if (cp != NULL) {
392 	      cp->c_flags &= ~C_VATTR;
393 	      coda_nc_zapParentfid(&out->coda_zapdir.Fid, IS_DOWNCALL);
394 
395 	      CODADEBUG(CODA_ZAPDIR, myprintf((
396 		    "zapdir: fid = %s, refcnt = %d\n",
397 		    coda_f2s(&cp->c_fid), CTOV(cp)->v_usecount - 1)););
398 	      if (CTOV(cp)->v_usecount == 1) {
399 		  cp->c_flags |= C_PURGING;
400 	      }
401 	      mutex_exit(&cp->c_lock);
402 	      vrele(CTOV(cp));
403 	  }
404 
405 	  return(0);
406       }
407 
408       case CODA_PURGEFID : {
409 	  struct cnode *cp;
410 
411 	  error = 0;
412 	  coda_clstat.ncalls++;
413 	  coda_clstat.reqs[CODA_PURGEFID]++;
414 
415 	  cp = coda_find(&out->coda_purgefid.Fid);
416 	  if (cp != NULL) {
417 	      if (IS_DIR(out->coda_purgefid.Fid)) { /* Vnode is a directory */
418 		  coda_nc_zapParentfid(&out->coda_purgefid.Fid,
419 				     IS_DOWNCALL);
420 	      }
421 	      cp->c_flags &= ~C_VATTR;
422 	      coda_nc_zapfid(&out->coda_purgefid.Fid, IS_DOWNCALL);
423 	      if (!(IS_DIR(out->coda_purgefid.Fid))
424 		  && (CTOV(cp)->v_iflag & VI_TEXT)) {
425 
426 		  error = coda_vmflush(cp);
427 	      }
428 	      CODADEBUG(CODA_PURGEFID, myprintf((
429 			 "purgefid: fid = %s, refcnt = %d, error = %d\n",
430 			 coda_f2s(&cp->c_fid), CTOV(cp)->v_usecount - 1, error)););
431 	      if (CTOV(cp)->v_usecount == 1) {
432 		  cp->c_flags |= C_PURGING;
433 	      }
434 	      mutex_exit(&cp->c_lock);
435 	      vrele(CTOV(cp));
436 	  }
437 	  return(error);
438       }
439 
440       case CODA_REPLACE : {
441 	  struct cnode *cp = NULL;
442 
443 	  coda_clstat.ncalls++;
444 	  coda_clstat.reqs[CODA_REPLACE]++;
445 
446 	  cp = coda_find(&out->coda_replace.OldFid);
447 	  if (cp != NULL) {
448 	      error = vcache_rekey_enter(CTOV(cp)->v_mount, CTOV(cp),
449 		  &out->coda_replace.OldFid, sizeof(CodaFid),
450 		  &out->coda_replace.NewFid, sizeof(CodaFid));
451 	      if (error) {
452 		  mutex_exit(&cp->c_lock);
453 		  vrele(CTOV(cp));
454 		  return error;
455 	      }
456 	      cp->c_fid = out->coda_replace.NewFid;
457 	      vcache_rekey_exit(CTOV(cp)->v_mount, CTOV(cp),
458 		  &out->coda_replace.OldFid, sizeof(CodaFid),
459 		  &cp->c_fid, sizeof(CodaFid));
460 
461 	      CODADEBUG(CODA_REPLACE, myprintf((
462 			"replace: oldfid = %s, newfid = %s, cp = %p\n",
463 			coda_f2s(&out->coda_replace.OldFid),
464 			coda_f2s(&cp->c_fid), cp));)
465 	      mutex_exit(&cp->c_lock);
466 	      vrele(CTOV(cp));
467 	  }
468 	  return (0);
469       }
470       default:
471       	myprintf(("handleDownCall: unknown opcode %d\n", opcode));
472 	return (EINVAL);
473     }
474 }
475 
476 /* coda_grab_vnode: lives in either cfs_mach.c or cfs_nbsd.c */
477 
478 int
479 coda_vmflush(struct cnode *cp)
480 {
481     return 0;
482 }
483 
484 
485 /*
486  * kernel-internal debugging switches
487  */
488 
489 void coda_debugon(void)
490 {
491     codadebug = -1;
492     coda_nc_debug = -1;
493     coda_vnop_print_entry = 1;
494     coda_psdev_print_entry = 1;
495     coda_vfsop_print_entry = 1;
496 }
497 
498 void coda_debugoff(void)
499 {
500     codadebug = 0;
501     coda_nc_debug = 0;
502     coda_vnop_print_entry = 0;
503     coda_psdev_print_entry = 0;
504     coda_vfsop_print_entry = 0;
505 }
506 
507 /* How to print a ucred */
508 void
509 coda_print_cred(kauth_cred_t cred)
510 {
511 
512 	uint16_t ngroups;
513 	int i;
514 
515 	myprintf(("ref %d\tuid %d\n", kauth_cred_getrefcnt(cred),
516 		 kauth_cred_geteuid(cred)));
517 
518 	ngroups = kauth_cred_ngroups(cred);
519 	for (i=0; i < ngroups; i++)
520 		myprintf(("\tgroup %d: (%d)\n", i, kauth_cred_group(cred, i)));
521 	myprintf(("\n"));
522 
523 }
524 
525 /*
526  * Utilities used by both client and server
527  * Standard levels:
528  * 0) no debugging
529  * 1) hard failures
530  * 2) soft failures
531  * 3) current test software
532  * 4) main procedure entry points
533  * 5) main procedure exit points
534  * 6) utility procedure entry points
535  * 7) utility procedure exit points
536  * 8) obscure procedure entry points
537  * 9) obscure procedure exit points
538  * 10) random stuff
539  * 11) all <= 1
540  * 12) all <= 2
541  * 13) all <= 3
542  * ...
543  */
544