xref: /netbsd/sys/coda/coda_subr.c (revision 6550d01e)
1 /*	$NetBSD: coda_subr.c,v 1.24 2007/10/10 20:42:21 ad 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 1.24 2007/10/10 20:42:21 ad 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(struct cnode *cp)
126 {
127 
128     CNODE_NEXT(cp) = coda_freelist;
129     coda_freelist = cp;
130 }
131 
132 /*
133  * Put a cnode in the hash table
134  */
135 void
136 coda_save(struct cnode *cp)
137 {
138 	CNODE_NEXT(cp) = coda_cache[coda_hash(&cp->c_fid)];
139 	coda_cache[coda_hash(&cp->c_fid)] = cp;
140 }
141 
142 /*
143  * Remove a cnode from the hash table
144  */
145 void
146 coda_unsave(struct cnode *cp)
147 {
148     struct cnode *ptr;
149     struct cnode *ptrprev = NULL;
150 
151     ptr = coda_cache[coda_hash(&cp->c_fid)];
152     while (ptr != NULL) {
153 	if (ptr == cp) {
154 	    if (ptrprev == NULL) {
155 		coda_cache[coda_hash(&cp->c_fid)]
156 		    = CNODE_NEXT(ptr);
157 	    } else {
158 		CNODE_NEXT(ptrprev) = CNODE_NEXT(ptr);
159 	    }
160 	    CNODE_NEXT(cp) = (struct cnode *)NULL;
161 
162 	    return;
163 	}
164 	ptrprev = ptr;
165 	ptr = CNODE_NEXT(ptr);
166     }
167 }
168 
169 /*
170  * Lookup a cnode by fid. If the cnode is dying, it is bogus so skip it.
171  * NOTE: this allows multiple cnodes with same fid -- dcs 1/25/95
172  */
173 struct cnode *
174 coda_find(CodaFid *fid)
175 {
176     struct cnode *cp;
177 
178     cp = coda_cache[coda_hash(fid)];
179     while (cp) {
180     	if (coda_fid_eq(&(cp->c_fid), fid) &&
181 	    (!IS_UNMOUNTING(cp)))
182 	    {
183 		coda_active++;
184 		return(cp);
185 	    }
186 	cp = CNODE_NEXT(cp);
187     }
188     return(NULL);
189 }
190 
191 /*
192  * coda_kill is called as a side effect to vcopen. To prevent any
193  * cnodes left around from an earlier run of a venus or warden from
194  * causing problems with the new instance, mark any outstanding cnodes
195  * as dying. Future operations on these cnodes should fail (excepting
196  * coda_inactive of course!). Since multiple venii/wardens can be
197  * running, only kill the cnodes for a particular entry in the
198  * coda_mnttbl. -- DCS 12/1/94 */
199 
200 int
201 coda_kill(struct mount *whoIam, enum dc_status dcstat)
202 {
203 	int hash, count = 0;
204 	struct cnode *cp;
205 
206 	/*
207 	 * Algorithm is as follows:
208 	 *     Second, flush whatever vnodes we can from the name cache.
209 	 *
210 	 *     Finally, step through whatever is left and mark them dying.
211 	 *        This prevents any operation at all.
212 
213 	 */
214 
215 	/* This is slightly overkill, but should work. Eventually it'd be
216 	 * nice to only flush those entries from the namecache that
217 	 * reference a vnode in this vfs.  */
218 	coda_nc_flush(dcstat);
219 
220 	for (hash = 0; hash < CODA_CACHESIZE; hash++) {
221 		for (cp = coda_cache[hash]; cp != NULL; cp = CNODE_NEXT(cp)) {
222 			if (CTOV(cp)->v_mount == whoIam) {
223 #ifdef	DEBUG
224 				printf("coda_kill: vp %p, cp %p\n", CTOV(cp), cp);
225 #endif
226 				count++;
227 				CODADEBUG(CODA_FLUSH,
228 					 myprintf(("Live cnode fid %s flags %d count %d\n",
229 						   coda_f2s(&cp->c_fid),
230 						   cp->c_flags,
231 						   CTOV(cp)->v_usecount)); );
232 			}
233 		}
234 	}
235 	return count;
236 }
237 
238 /*
239  * There are two reasons why a cnode may be in use, it may be in the
240  * name cache or it may be executing.
241  */
242 void
243 coda_flush(enum dc_status dcstat)
244 {
245     int hash;
246     struct cnode *cp;
247 
248     coda_clstat.ncalls++;
249     coda_clstat.reqs[CODA_FLUSH]++;
250 
251     coda_nc_flush(dcstat);	    /* flush files from the name cache */
252 
253     for (hash = 0; hash < CODA_CACHESIZE; hash++) {
254 	for (cp = coda_cache[hash]; cp != NULL; cp = CNODE_NEXT(cp)) {
255 	    if (!IS_DIR(cp->c_fid)) /* only files can be executed */
256 		coda_vmflush(cp);
257 	}
258     }
259 }
260 
261 /*
262  * As a debugging measure, print out any cnodes that lived through a
263  * name cache flush.
264  */
265 void
266 coda_testflush(void)
267 {
268     int hash;
269     struct cnode *cp;
270 
271     for (hash = 0; hash < CODA_CACHESIZE; hash++) {
272 	for (cp = coda_cache[hash];
273 	     cp != NULL;
274 	     cp = CNODE_NEXT(cp)) {
275 	    myprintf(("Live cnode fid %s count %d\n",
276 		      coda_f2s(&cp->c_fid), CTOV(cp)->v_usecount));
277 	}
278     }
279 }
280 
281 /*
282  *     First, step through all cnodes and mark them unmounting.
283  *         NetBSD kernels may try to fsync them now that venus
284  *         is dead, which would be a bad thing.
285  *
286  */
287 void
288 coda_unmounting(struct mount *whoIam)
289 {
290 	int hash;
291 	struct cnode *cp;
292 
293 	for (hash = 0; hash < CODA_CACHESIZE; hash++) {
294 		for (cp = coda_cache[hash]; cp != NULL; cp = CNODE_NEXT(cp)) {
295 			if (CTOV(cp)->v_mount == whoIam) {
296 				if (cp->c_flags & (C_LOCKED|C_WANTED)) {
297 					printf("coda_unmounting: Unlocking %p\n", cp);
298 					cp->c_flags &= ~(C_LOCKED|C_WANTED);
299 					wakeup((void *) cp);
300 				}
301 				cp->c_flags |= C_UNMOUNTING;
302 			}
303 		}
304 	}
305 }
306 
307 #ifdef	DEBUG
308 void
309 coda_checkunmounting(struct mount *mp)
310 {
311 	struct vnode *vp;
312 	struct cnode *cp;
313 	int count = 0, bad = 0;
314 loop:
315 	TAILQ_FOREACH(vp, &mp->mnt_vnodelist, v_mntvnodes) {
316 		if (vp->v_mount != mp)
317 			goto loop;
318 		cp = VTOC(vp);
319 		count++;
320 		if (!(cp->c_flags & C_UNMOUNTING)) {
321 			bad++;
322 			printf("vp %p, cp %p missed\n", vp, cp);
323 			cp->c_flags |= C_UNMOUNTING;
324 		}
325 	}
326 }
327 
328 void
329 coda_cacheprint(struct mount *whoIam)
330 {
331 	int hash;
332 	struct cnode *cp;
333 	int count = 0;
334 
335 	printf("coda_cacheprint: coda_ctlvp %p, cp %p", coda_ctlvp, VTOC(coda_ctlvp));
336 	coda_nc_name(VTOC(coda_ctlvp));
337 	printf("\n");
338 
339 	for (hash = 0; hash < CODA_CACHESIZE; hash++) {
340 		for (cp = coda_cache[hash]; cp != NULL; cp = CNODE_NEXT(cp)) {
341 			if (CTOV(cp)->v_mount == whoIam) {
342 				printf("coda_cacheprint: vp %p, cp %p", CTOV(cp), cp);
343 				coda_nc_name(cp);
344 				printf("\n");
345 				count++;
346 			}
347 		}
348 	}
349 	printf("coda_cacheprint: count %d\n", count);
350 }
351 #endif
352 
353 /*
354  * There are 6 cases where invalidations occur. The semantics of each
355  * is listed here.
356  *
357  * CODA_FLUSH     -- flush all entries from the name cache and the cnode cache.
358  * CODA_PURGEUSER -- flush all entries from the name cache for a specific user
359  *                  This call is a result of token expiration.
360  *
361  * The next two are the result of callbacks on a file or directory.
362  * CODA_ZAPDIR    -- flush the attributes for the dir from its cnode.
363  *                  Zap all children of this directory from the namecache.
364  * CODA_ZAPFILE   -- flush the attributes for a file.
365  *
366  * The fifth is a result of Venus detecting an inconsistent file.
367  * CODA_PURGEFID  -- flush the attribute for the file
368  *                  If it is a dir (odd vnode), purge its
369  *                  children from the namecache
370  *                  remove the file from the namecache.
371  *
372  * The sixth allows Venus to replace local fids with global ones
373  * during reintegration.
374  *
375  * CODA_REPLACE -- replace one CodaFid with another throughout the name cache
376  */
377 
378 int handleDownCall(int opcode, union outputArgs *out)
379 {
380     int error;
381 
382     /* Handle invalidate requests. */
383     switch (opcode) {
384       case CODA_FLUSH : {
385 
386 	  coda_flush(IS_DOWNCALL);
387 
388 	  CODADEBUG(CODA_FLUSH,coda_testflush();)    /* print remaining cnodes */
389 	      return(0);
390       }
391 
392       case CODA_PURGEUSER : {
393 	  coda_clstat.ncalls++;
394 	  coda_clstat.reqs[CODA_PURGEUSER]++;
395 
396 	  /* XXX - need to prevent fsync's */
397 #ifdef CODA_COMPAT_5
398 	  coda_nc_purge_user(out->coda_purgeuser.cred.cr_uid, IS_DOWNCALL);
399 #else
400 	  coda_nc_purge_user(out->coda_purgeuser.uid, IS_DOWNCALL);
401 #endif
402 	  return(0);
403       }
404 
405       case CODA_ZAPFILE : {
406 	  struct cnode *cp;
407 
408 	  error = 0;
409 	  coda_clstat.ncalls++;
410 	  coda_clstat.reqs[CODA_ZAPFILE]++;
411 
412 	  cp = coda_find(&out->coda_zapfile.Fid);
413 	  if (cp != NULL) {
414 	      vref(CTOV(cp));
415 
416 	      cp->c_flags &= ~C_VATTR;
417 	      if (CTOV(cp)->v_iflag & VI_TEXT)
418 		  error = coda_vmflush(cp);
419 	      CODADEBUG(CODA_ZAPFILE, myprintf((
420 		    "zapfile: fid = %s, refcnt = %d, error = %d\n",
421 		    coda_f2s(&cp->c_fid), CTOV(cp)->v_usecount - 1, error)););
422 	      if (CTOV(cp)->v_usecount == 1) {
423 		  cp->c_flags |= C_PURGING;
424 	      }
425 	      vrele(CTOV(cp));
426 	  }
427 
428 	  return(error);
429       }
430 
431       case CODA_ZAPDIR : {
432 	  struct cnode *cp;
433 
434 	  coda_clstat.ncalls++;
435 	  coda_clstat.reqs[CODA_ZAPDIR]++;
436 
437 	  cp = coda_find(&out->coda_zapdir.Fid);
438 	  if (cp != NULL) {
439 	      vref(CTOV(cp));
440 
441 	      cp->c_flags &= ~C_VATTR;
442 	      coda_nc_zapParentfid(&out->coda_zapdir.Fid, IS_DOWNCALL);
443 
444 	      CODADEBUG(CODA_ZAPDIR, myprintf((
445 		    "zapdir: fid = %s, refcnt = %d\n",
446 		    coda_f2s(&cp->c_fid), CTOV(cp)->v_usecount - 1)););
447 	      if (CTOV(cp)->v_usecount == 1) {
448 		  cp->c_flags |= C_PURGING;
449 	      }
450 	      vrele(CTOV(cp));
451 	  }
452 
453 	  return(0);
454       }
455 
456       case CODA_PURGEFID : {
457 	  struct cnode *cp;
458 
459 	  error = 0;
460 	  coda_clstat.ncalls++;
461 	  coda_clstat.reqs[CODA_PURGEFID]++;
462 
463 	  cp = coda_find(&out->coda_purgefid.Fid);
464 	  if (cp != NULL) {
465 	      vref(CTOV(cp));
466 	      if (IS_DIR(out->coda_purgefid.Fid)) { /* Vnode is a directory */
467 		  coda_nc_zapParentfid(&out->coda_purgefid.Fid,
468 				     IS_DOWNCALL);
469 	      }
470 	      cp->c_flags &= ~C_VATTR;
471 	      coda_nc_zapfid(&out->coda_purgefid.Fid, IS_DOWNCALL);
472 	      if (!(IS_DIR(out->coda_purgefid.Fid))
473 		  && (CTOV(cp)->v_iflag & VI_TEXT)) {
474 
475 		  error = coda_vmflush(cp);
476 	      }
477 	      CODADEBUG(CODA_PURGEFID, myprintf((
478 			 "purgefid: fid = %s, refcnt = %d, error = %d\n",
479 			 coda_f2s(&cp->c_fid), CTOV(cp)->v_usecount - 1, error)););
480 	      if (CTOV(cp)->v_usecount == 1) {
481 		  cp->c_flags |= C_PURGING;
482 	      }
483 	      vrele(CTOV(cp));
484 	  }
485 	  return(error);
486       }
487 
488       case CODA_REPLACE : {
489 	  struct cnode *cp = NULL;
490 
491 	  coda_clstat.ncalls++;
492 	  coda_clstat.reqs[CODA_REPLACE]++;
493 
494 	  cp = coda_find(&out->coda_replace.OldFid);
495 	  if (cp != NULL) {
496 	      /* remove the cnode from the hash table, replace the fid, and reinsert */
497 	      vref(CTOV(cp));
498 	      coda_unsave(cp);
499 	      cp->c_fid = out->coda_replace.NewFid;
500 	      coda_save(cp);
501 
502 	      CODADEBUG(CODA_REPLACE, myprintf((
503 			"replace: oldfid = %s, newfid = %s, cp = %p\n",
504 			coda_f2s(&out->coda_replace.OldFid),
505 			coda_f2s(&cp->c_fid), cp));)
506 	      vrele(CTOV(cp));
507 	  }
508 	  return (0);
509       }
510       default:
511       	myprintf(("handleDownCall: unknown opcode %d\n", opcode));
512 	return (EINVAL);
513     }
514 }
515 
516 /* coda_grab_vnode: lives in either cfs_mach.c or cfs_nbsd.c */
517 
518 int
519 coda_vmflush(struct cnode *cp)
520 {
521     return 0;
522 }
523 
524 
525 /*
526  * kernel-internal debugging switches
527  */
528 
529 void coda_debugon(void)
530 {
531     codadebug = -1;
532     coda_nc_debug = -1;
533     coda_vnop_print_entry = 1;
534     coda_psdev_print_entry = 1;
535     coda_vfsop_print_entry = 1;
536 }
537 
538 void coda_debugoff(void)
539 {
540     codadebug = 0;
541     coda_nc_debug = 0;
542     coda_vnop_print_entry = 0;
543     coda_psdev_print_entry = 0;
544     coda_vfsop_print_entry = 0;
545 }
546 
547 /*
548  * Utilities used by both client and server
549  * Standard levels:
550  * 0) no debugging
551  * 1) hard failures
552  * 2) soft failures
553  * 3) current test software
554  * 4) main procedure entry points
555  * 5) main procedure exit points
556  * 6) utility procedure entry points
557  * 7) utility procedure exit points
558  * 8) obscure procedure entry points
559  * 9) obscure procedure exit points
560  * 10) random stuff
561  * 11) all <= 1
562  * 12) all <= 2
563  * 13) all <= 3
564  * ...
565  */
566