xref: /netbsd-src/sys/coda/coda_subr.c (revision 23c8222edbfb0f0932d88a8351d3a0cf817dfb9e)
1 /*	$NetBSD: coda_subr.c,v 1.16 2003/08/28 05:55:19 mrg 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 1.16 2003/08/28 05:55:19 mrg 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 
67 #include <coda/coda.h>
68 #include <coda/cnode.h>
69 #include <coda/coda_subr.h>
70 #include <coda/coda_namecache.h>
71 
72 #ifdef _KERNEL_OPT
73 #include "opt_coda_compat.h"
74 #endif
75 
76 int coda_active = 0;
77 int coda_reuse = 0;
78 int coda_new = 0;
79 
80 struct cnode *coda_freelist = NULL;
81 struct cnode *coda_cache[CODA_CACHESIZE];
82 
83 #define	CNODE_NEXT(cp)	((cp)->c_next)
84 
85 #ifdef CODA_COMPAT_5
86 #define coda_hash(fid) \
87     (((fid)->Volume + (fid)->Vnode) & (CODA_CACHESIZE-1))
88 #define IS_DIR(cnode)        (cnode.Vnode & 0x1)
89 #else
90 #define coda_hash(fid) \
91     (coda_f2i(fid) & (CODA_CACHESIZE-1))
92 #define IS_DIR(cnode)        (cnode.opaque[2] & 0x1)
93 #endif
94 
95 /*
96  * Allocate a cnode.
97  */
98 struct cnode *
99 coda_alloc(void)
100 {
101     struct cnode *cp;
102 
103     if (coda_freelist) {
104 	cp = coda_freelist;
105 	coda_freelist = CNODE_NEXT(cp);
106 	coda_reuse++;
107     }
108     else {
109 	CODA_ALLOC(cp, struct cnode *, sizeof(struct cnode));
110 	/* NetBSD vnodes don't have any Pager info in them ('cause there are
111 	   no external pagers, duh!) */
112 #define VNODE_VM_INFO_INIT(vp)         /* MT */
113 	VNODE_VM_INFO_INIT(CTOV(cp));
114 	coda_new++;
115     }
116     memset(cp, 0, sizeof (struct cnode));
117 
118     return(cp);
119 }
120 
121 /*
122  * Deallocate a cnode.
123  */
124 void
125 coda_free(cp)
126      struct cnode *cp;
127 {
128 
129     CNODE_NEXT(cp) = coda_freelist;
130     coda_freelist = cp;
131 }
132 
133 /*
134  * Put a cnode in the hash table
135  */
136 void
137 coda_save(cp)
138      struct cnode *cp;
139 {
140 	CNODE_NEXT(cp) = coda_cache[coda_hash(&cp->c_fid)];
141 	coda_cache[coda_hash(&cp->c_fid)] = cp;
142 }
143 
144 /*
145  * Remove a cnode from the hash table
146  */
147 void
148 coda_unsave(cp)
149      struct cnode *cp;
150 {
151     struct cnode *ptr;
152     struct cnode *ptrprev = NULL;
153 
154     ptr = coda_cache[coda_hash(&cp->c_fid)];
155     while (ptr != NULL) {
156 	if (ptr == cp) {
157 	    if (ptrprev == NULL) {
158 		coda_cache[coda_hash(&cp->c_fid)]
159 		    = CNODE_NEXT(ptr);
160 	    } else {
161 		CNODE_NEXT(ptrprev) = CNODE_NEXT(ptr);
162 	    }
163 	    CNODE_NEXT(cp) = (struct cnode *)NULL;
164 
165 	    return;
166 	}
167 	ptrprev = ptr;
168 	ptr = CNODE_NEXT(ptr);
169     }
170 }
171 
172 /*
173  * Lookup a cnode by fid. If the cnode is dying, it is bogus so skip it.
174  * NOTE: this allows multiple cnodes with same fid -- dcs 1/25/95
175  */
176 struct cnode *
177 coda_find(fid)
178      CodaFid *fid;
179 {
180     struct cnode *cp;
181 
182     cp = coda_cache[coda_hash(fid)];
183     while (cp) {
184     	if (coda_fid_eq(&(cp->c_fid), fid) &&
185 	    (!IS_UNMOUNTING(cp)))
186 	    {
187 		coda_active++;
188 		return(cp);
189 	    }
190 	cp = CNODE_NEXT(cp);
191     }
192     return(NULL);
193 }
194 
195 /*
196  * coda_kill is called as a side effect to vcopen. To prevent any
197  * cnodes left around from an earlier run of a venus or warden from
198  * causing problems with the new instance, mark any outstanding cnodes
199  * as dying. Future operations on these cnodes should fail (excepting
200  * coda_inactive of course!). Since multiple venii/wardens can be
201  * running, only kill the cnodes for a particular entry in the
202  * coda_mnttbl. -- DCS 12/1/94 */
203 
204 int
205 coda_kill(whoIam, dcstat)
206 	struct mount *whoIam;
207 	enum dc_status dcstat;
208 {
209 	int hash, count = 0;
210 	struct cnode *cp;
211 
212 	/*
213 	 * Algorithm is as follows:
214 	 *     Second, flush whatever vnodes we can from the name cache.
215 	 *
216 	 *     Finally, step through whatever is left and mark them dying.
217 	 *        This prevents any operation at all.
218 
219 	 */
220 
221 	/* This is slightly overkill, but should work. Eventually it'd be
222 	 * nice to only flush those entries from the namecache that
223 	 * reference a vnode in this vfs.  */
224 	coda_nc_flush(dcstat);
225 
226 	for (hash = 0; hash < CODA_CACHESIZE; hash++) {
227 		for (cp = coda_cache[hash]; cp != NULL; cp = CNODE_NEXT(cp)) {
228 			if (CTOV(cp)->v_mount == whoIam) {
229 #ifdef	DEBUG
230 				printf("coda_kill: vp %p, cp %p\n", CTOV(cp), cp);
231 #endif
232 				count++;
233 				CODADEBUG(CODA_FLUSH,
234 					 myprintf(("Live cnode fid %s flags %d count %d\n",
235 						   coda_f2s(&cp->c_fid),
236 						   cp->c_flags,
237 						   CTOV(cp)->v_usecount)); );
238 			}
239 		}
240 	}
241 	return count;
242 }
243 
244 /*
245  * There are two reasons why a cnode may be in use, it may be in the
246  * name cache or it may be executing.
247  */
248 void
249 coda_flush(dcstat)
250 	enum dc_status dcstat;
251 {
252     int hash;
253     struct cnode *cp;
254 
255     coda_clstat.ncalls++;
256     coda_clstat.reqs[CODA_FLUSH]++;
257 
258     coda_nc_flush(dcstat);	    /* flush files from the name cache */
259 
260     for (hash = 0; hash < CODA_CACHESIZE; hash++) {
261 	for (cp = coda_cache[hash]; cp != NULL; cp = CNODE_NEXT(cp)) {
262 	    if (!IS_DIR(cp->c_fid)) /* only files can be executed */
263 		coda_vmflush(cp);
264 	}
265     }
266 }
267 
268 /*
269  * As a debugging measure, print out any cnodes that lived through a
270  * name cache flush.
271  */
272 void
273 coda_testflush(void)
274 {
275     int hash;
276     struct cnode *cp;
277 
278     for (hash = 0; hash < CODA_CACHESIZE; hash++) {
279 	for (cp = coda_cache[hash];
280 	     cp != NULL;
281 	     cp = CNODE_NEXT(cp)) {
282 	    myprintf(("Live cnode fid %s count %d\n",
283 		      coda_f2s(&cp->c_fid), CTOV(cp)->v_usecount));
284 	}
285     }
286 }
287 
288 /*
289  *     First, step through all cnodes and mark them unmounting.
290  *         NetBSD kernels may try to fsync them now that venus
291  *         is dead, which would be a bad thing.
292  *
293  */
294 void
295 coda_unmounting(whoIam)
296 	struct mount *whoIam;
297 {
298 	int hash;
299 	struct cnode *cp;
300 
301 	for (hash = 0; hash < CODA_CACHESIZE; hash++) {
302 		for (cp = coda_cache[hash]; cp != NULL; cp = CNODE_NEXT(cp)) {
303 			if (CTOV(cp)->v_mount == whoIam) {
304 				if (cp->c_flags & (C_LOCKED|C_WANTED)) {
305 					printf("coda_unmounting: Unlocking %p\n", cp);
306 					cp->c_flags &= ~(C_LOCKED|C_WANTED);
307 					wakeup((caddr_t) cp);
308 				}
309 				cp->c_flags |= C_UNMOUNTING;
310 			}
311 		}
312 	}
313 }
314 
315 #ifdef	DEBUG
316 void
317 coda_checkunmounting(mp)
318 	struct mount *mp;
319 {
320 	struct vnode *vp, *nvp;
321 	struct cnode *cp;
322 	int count = 0, bad = 0;
323 loop:
324 	for (vp = mp->mnt_vnodelist.lh_first; vp; vp = nvp) {
325 		if (vp->v_mount != mp)
326 			goto loop;
327 		nvp = vp->v_mntvnodes.le_next;
328 		cp = VTOC(vp);
329 		count++;
330 		if (!(cp->c_flags & C_UNMOUNTING)) {
331 			bad++;
332 			printf("vp %p, cp %p missed\n", vp, cp);
333 			cp->c_flags |= C_UNMOUNTING;
334 		}
335 	}
336 }
337 
338 void
339 coda_cacheprint(whoIam)
340 	struct mount *whoIam;
341 {
342 	int hash;
343 	struct cnode *cp;
344 	int count = 0;
345 
346 	printf("coda_cacheprint: coda_ctlvp %p, cp %p", coda_ctlvp, VTOC(coda_ctlvp));
347 	coda_nc_name(VTOC(coda_ctlvp));
348 	printf("\n");
349 
350 	for (hash = 0; hash < CODA_CACHESIZE; hash++) {
351 		for (cp = coda_cache[hash]; cp != NULL; cp = CNODE_NEXT(cp)) {
352 			if (CTOV(cp)->v_mount == whoIam) {
353 				printf("coda_cacheprint: vp %p, cp %p", CTOV(cp), cp);
354 				coda_nc_name(cp);
355 				printf("\n");
356 				count++;
357 			}
358 		}
359 	}
360 	printf("coda_cacheprint: count %d\n", count);
361 }
362 #endif
363 
364 /*
365  * There are 6 cases where invalidations occur. The semantics of each
366  * is listed here.
367  *
368  * CODA_FLUSH     -- flush all entries from the name cache and the cnode cache.
369  * CODA_PURGEUSER -- flush all entries from the name cache for a specific user
370  *                  This call is a result of token expiration.
371  *
372  * The next two are the result of callbacks on a file or directory.
373  * CODA_ZAPDIR    -- flush the attributes for the dir from its cnode.
374  *                  Zap all children of this directory from the namecache.
375  * CODA_ZAPFILE   -- flush the attributes for a file.
376  *
377  * The fifth is a result of Venus detecting an inconsistent file.
378  * CODA_PURGEFID  -- flush the attribute for the file
379  *                  If it is a dir (odd vnode), purge its
380  *                  children from the namecache
381  *                  remove the file from the namecache.
382  *
383  * The sixth allows Venus to replace local fids with global ones
384  * during reintegration.
385  *
386  * CODA_REPLACE -- replace one CodaFid with another throughout the name cache
387  */
388 
389 int handleDownCall(opcode, out)
390      int opcode; union outputArgs *out;
391 {
392     int error;
393 
394     /* Handle invalidate requests. */
395     switch (opcode) {
396       case CODA_FLUSH : {
397 
398 	  coda_flush(IS_DOWNCALL);
399 
400 	  CODADEBUG(CODA_FLUSH,coda_testflush();)    /* print remaining cnodes */
401 	      return(0);
402       }
403 
404       case CODA_PURGEUSER : {
405 	  coda_clstat.ncalls++;
406 	  coda_clstat.reqs[CODA_PURGEUSER]++;
407 
408 	  /* XXX - need to prevent fsync's */
409 #ifdef CODA_COMPAT_5
410 	  coda_nc_purge_user(out->coda_purgeuser.cred.cr_uid, IS_DOWNCALL);
411 #else
412 	  coda_nc_purge_user(out->coda_purgeuser.uid, IS_DOWNCALL);
413 #endif
414 	  return(0);
415       }
416 
417       case CODA_ZAPFILE : {
418 	  struct cnode *cp;
419 
420 	  error = 0;
421 	  coda_clstat.ncalls++;
422 	  coda_clstat.reqs[CODA_ZAPFILE]++;
423 
424 	  cp = coda_find(&out->coda_zapfile.Fid);
425 	  if (cp != NULL) {
426 	      vref(CTOV(cp));
427 
428 	      cp->c_flags &= ~C_VATTR;
429 	      if (CTOV(cp)->v_flag & VTEXT)
430 		  error = coda_vmflush(cp);
431 	      CODADEBUG(CODA_ZAPFILE, myprintf((
432 		    "zapfile: fid = %s, refcnt = %d, error = %d\n",
433 		    coda_f2s(&cp->c_fid), CTOV(cp)->v_usecount - 1, error)););
434 	      if (CTOV(cp)->v_usecount == 1) {
435 		  cp->c_flags |= C_PURGING;
436 	      }
437 	      vrele(CTOV(cp));
438 	  }
439 
440 	  return(error);
441       }
442 
443       case CODA_ZAPDIR : {
444 	  struct cnode *cp;
445 
446 	  coda_clstat.ncalls++;
447 	  coda_clstat.reqs[CODA_ZAPDIR]++;
448 
449 	  cp = coda_find(&out->coda_zapdir.Fid);
450 	  if (cp != NULL) {
451 	      vref(CTOV(cp));
452 
453 	      cp->c_flags &= ~C_VATTR;
454 	      coda_nc_zapParentfid(&out->coda_zapdir.Fid, IS_DOWNCALL);
455 
456 	      CODADEBUG(CODA_ZAPDIR, myprintf((
457 		    "zapdir: fid = %s, refcnt = %d\n",
458 		    coda_f2s(&cp->c_fid), CTOV(cp)->v_usecount - 1)););
459 	      if (CTOV(cp)->v_usecount == 1) {
460 		  cp->c_flags |= C_PURGING;
461 	      }
462 	      vrele(CTOV(cp));
463 	  }
464 
465 	  return(0);
466       }
467 
468       case CODA_PURGEFID : {
469 	  struct cnode *cp;
470 
471 	  error = 0;
472 	  coda_clstat.ncalls++;
473 	  coda_clstat.reqs[CODA_PURGEFID]++;
474 
475 	  cp = coda_find(&out->coda_purgefid.Fid);
476 	  if (cp != NULL) {
477 	      vref(CTOV(cp));
478 	      if (IS_DIR(out->coda_purgefid.Fid)) { /* Vnode is a directory */
479 		  coda_nc_zapParentfid(&out->coda_purgefid.Fid,
480 				     IS_DOWNCALL);
481 	      }
482 	      cp->c_flags &= ~C_VATTR;
483 	      coda_nc_zapfid(&out->coda_purgefid.Fid, IS_DOWNCALL);
484 	      if (!(IS_DIR(out->coda_purgefid.Fid))
485 		  && (CTOV(cp)->v_flag & VTEXT)) {
486 
487 		  error = coda_vmflush(cp);
488 	      }
489 	      CODADEBUG(CODA_PURGEFID, myprintf((
490 			 "purgefid: fid = %s, refcnt = %d, error = %d\n",
491 			 coda_f2s(&cp->c_fid), CTOV(cp)->v_usecount - 1, error)););
492 	      if (CTOV(cp)->v_usecount == 1) {
493 		  cp->c_flags |= C_PURGING;
494 	      }
495 	      vrele(CTOV(cp));
496 	  }
497 	  return(error);
498       }
499 
500       case CODA_REPLACE : {
501 	  struct cnode *cp = NULL;
502 
503 	  coda_clstat.ncalls++;
504 	  coda_clstat.reqs[CODA_REPLACE]++;
505 
506 	  cp = coda_find(&out->coda_replace.OldFid);
507 	  if (cp != NULL) {
508 	      /* remove the cnode from the hash table, replace the fid, and reinsert */
509 	      vref(CTOV(cp));
510 	      coda_unsave(cp);
511 	      cp->c_fid = out->coda_replace.NewFid;
512 	      coda_save(cp);
513 
514 	      CODADEBUG(CODA_REPLACE, myprintf((
515 			"replace: oldfid = %s, newfid = %s, cp = %p\n",
516 			coda_f2s(&out->coda_replace.OldFid),
517 			coda_f2s(&cp->c_fid), cp));)
518 	      vrele(CTOV(cp));
519 	  }
520 	  return (0);
521       }
522       default:
523       	myprintf(("handleDownCall: unknown opcode %d\n", opcode));
524 	return (EINVAL);
525     }
526 }
527 
528 /* coda_grab_vnode: lives in either cfs_mach.c or cfs_nbsd.c */
529 
530 int
531 coda_vmflush(cp)
532      struct cnode *cp;
533 {
534     return 0;
535 }
536 
537 
538 /*
539  * kernel-internal debugging switches
540  */
541 
542 void coda_debugon(void)
543 {
544     codadebug = -1;
545     coda_nc_debug = -1;
546     coda_vnop_print_entry = 1;
547     coda_psdev_print_entry = 1;
548     coda_vfsop_print_entry = 1;
549 }
550 
551 void coda_debugoff(void)
552 {
553     codadebug = 0;
554     coda_nc_debug = 0;
555     coda_vnop_print_entry = 0;
556     coda_psdev_print_entry = 0;
557     coda_vfsop_print_entry = 0;
558 }
559 
560 /*
561  * Utilities used by both client and server
562  * Standard levels:
563  * 0) no debugging
564  * 1) hard failures
565  * 2) soft failures
566  * 3) current test software
567  * 4) main procedure entry points
568  * 5) main procedure exit points
569  * 6) utility procedure entry points
570  * 7) utility procedure exit points
571  * 8) obscure procedure entry points
572  * 9) obscure procedure exit points
573  * 10) random stuff
574  * 11) all <= 1
575  * 12) all <= 2
576  * 13) all <= 3
577  * ...
578  */
579