coda_namecache.c revision 1.30 1 1.30 thorpej /* $NetBSD: coda_namecache.c,v 1.30 2024/05/17 23:57:46 thorpej Exp $ */
2 1.2 rvb
3 1.1 rvb /*
4 1.14 perry *
5 1.2 rvb * Coda: an Experimental Distributed File System
6 1.2 rvb * Release 3.1
7 1.14 perry *
8 1.2 rvb * Copyright (c) 1987-1998 Carnegie Mellon University
9 1.2 rvb * All Rights Reserved
10 1.14 perry *
11 1.2 rvb * Permission to use, copy, modify and distribute this software and its
12 1.2 rvb * documentation is hereby granted, provided that both the copyright
13 1.2 rvb * notice and this permission notice appear in all copies of the
14 1.2 rvb * software, derivative works or modified versions, and any portions
15 1.2 rvb * thereof, and that both notices appear in supporting documentation, and
16 1.2 rvb * that credit is given to Carnegie Mellon University in all documents
17 1.2 rvb * and publicity pertaining to direct or indirect use of this code or its
18 1.2 rvb * derivatives.
19 1.14 perry *
20 1.2 rvb * CODA IS AN EXPERIMENTAL SOFTWARE SYSTEM AND IS KNOWN TO HAVE BUGS,
21 1.2 rvb * SOME OF WHICH MAY HAVE SERIOUS CONSEQUENCES. CARNEGIE MELLON ALLOWS
22 1.2 rvb * FREE USE OF THIS SOFTWARE IN ITS "AS IS" CONDITION. CARNEGIE MELLON
23 1.2 rvb * DISCLAIMS ANY LIABILITY OF ANY KIND FOR ANY DAMAGES WHATSOEVER
24 1.2 rvb * RESULTING DIRECTLY OR INDIRECTLY FROM THE USE OF THIS SOFTWARE OR OF
25 1.2 rvb * ANY DERIVATIVE WORK.
26 1.14 perry *
27 1.2 rvb * Carnegie Mellon encourages users of this software to return any
28 1.2 rvb * improvements or extensions that they make, and to grant Carnegie
29 1.2 rvb * Mellon the rights to redistribute these changes without encumbrance.
30 1.14 perry *
31 1.14 perry * @(#) coda/coda_namecache.c,v 1.1.1.1 1998/08/29 21:26:45 rvb Exp $
32 1.2 rvb */
33 1.1 rvb
34 1.14 perry /*
35 1.1 rvb * Mach Operating System
36 1.1 rvb * Copyright (c) 1990 Carnegie-Mellon University
37 1.1 rvb * Copyright (c) 1989 Carnegie-Mellon University
38 1.1 rvb * All rights reserved. The CMU software License Agreement specifies
39 1.1 rvb * the terms and conditions for use and redistribution.
40 1.1 rvb */
41 1.1 rvb
42 1.1 rvb /*
43 1.1 rvb * This code was written for the Coda file system at Carnegie Mellon University.
44 1.1 rvb * Contributers include David Steere, James Kistler, and M. Satyanarayanan.
45 1.1 rvb */
46 1.1 rvb
47 1.1 rvb /*
48 1.3 rvb * This module contains the routines to implement the CODA name cache. The
49 1.14 perry * purpose of this cache is to reduce the cost of translating pathnames
50 1.1 rvb * into Vice FIDs. Each entry in the cache contains the name of the file,
51 1.1 rvb * the vnode (FID) of the parent directory, and the cred structure of the
52 1.1 rvb * user accessing the file.
53 1.1 rvb *
54 1.1 rvb * The first time a file is accessed, it is looked up by the local Venus
55 1.1 rvb * which first insures that the user has access to the file. In addition
56 1.1 rvb * we are guaranteed that Venus will invalidate any name cache entries in
57 1.1 rvb * case the user no longer should be able to access the file. For these
58 1.1 rvb * reasons we do not need to keep access list information as well as a
59 1.1 rvb * cred structure for each entry.
60 1.1 rvb *
61 1.1 rvb * The table can be accessed through the routines cnc_init(), cnc_enter(),
62 1.1 rvb * cnc_lookup(), cnc_rmfidcred(), cnc_rmfid(), cnc_rmcred(), and cnc_purge().
63 1.1 rvb * There are several other routines which aid in the implementation of the
64 1.1 rvb * hash table.
65 1.1 rvb */
66 1.1 rvb
67 1.1 rvb /*
68 1.1 rvb * NOTES: rvb@cs
69 1.1 rvb * 1. The name cache holds a reference to every vnode in it. Hence files can not be
70 1.1 rvb * closed or made inactive until they are released.
71 1.3 rvb * 2. coda_nc_name(cp) was added to get a name for a cnode pointer for debugging.
72 1.3 rvb * 3. coda_nc_find() has debug code to detect when entries are stored with different
73 1.1 rvb * credentials. We don't understand yet, if/how entries are NOT EQ but still
74 1.1 rvb * EQUAL
75 1.1 rvb * 4. I wonder if this name cache could be replace by the vnode name cache.
76 1.1 rvb * The latter has no zapping functions, so probably not.
77 1.1 rvb */
78 1.11 lukem
79 1.11 lukem #include <sys/cdefs.h>
80 1.30 thorpej __KERNEL_RCSID(0, "$NetBSD: coda_namecache.c,v 1.30 2024/05/17 23:57:46 thorpej Exp $");
81 1.1 rvb
82 1.1 rvb #include <sys/param.h>
83 1.1 rvb #include <sys/errno.h>
84 1.1 rvb #include <sys/select.h>
85 1.18 elad #include <sys/kauth.h>
86 1.1 rvb
87 1.4 rvb #include <coda/coda.h>
88 1.4 rvb #include <coda/cnode.h>
89 1.4 rvb #include <coda/coda_namecache.h>
90 1.25 christos #include <coda/coda_subr.h>
91 1.5 rvb
92 1.14 perry /*
93 1.1 rvb * Declaration of the name cache data structure.
94 1.1 rvb */
95 1.1 rvb
96 1.3 rvb int coda_nc_use = 1; /* Indicate use of CODA Name Cache */
97 1.1 rvb
98 1.3 rvb int coda_nc_size = CODA_NC_CACHESIZE; /* size of the cache */
99 1.3 rvb int coda_nc_hashsize = CODA_NC_HASHSIZE; /* size of the primary hash */
100 1.1 rvb
101 1.3 rvb struct coda_cache *coda_nc_heap; /* pointer to the cache entries */
102 1.3 rvb struct coda_hash *coda_nc_hash; /* hash table of cfscache pointers */
103 1.3 rvb struct coda_lru coda_nc_lru; /* head of lru chain */
104 1.1 rvb
105 1.3 rvb struct coda_nc_statistics coda_nc_stat; /* Keep various stats */
106 1.1 rvb
107 1.14 perry /*
108 1.1 rvb * for testing purposes
109 1.1 rvb */
110 1.3 rvb int coda_nc_debug = 0;
111 1.1 rvb
112 1.1 rvb /*
113 1.3 rvb * Entry points for the CODA Name Cache
114 1.1 rvb */
115 1.3 rvb static struct coda_cache *
116 1.3 rvb coda_nc_find(struct cnode *dcp, const char *name, int namelen,
117 1.18 elad kauth_cred_t cred, int hash);
118 1.1 rvb static void
119 1.3 rvb coda_nc_remove(struct coda_cache *cncp, enum dc_status dcstat);
120 1.1 rvb
121 1.14 perry /*
122 1.1 rvb * Initialize the cache, the LRU structure and the Hash structure(s)
123 1.1 rvb */
124 1.1 rvb
125 1.3 rvb #define TOTAL_CACHE_SIZE (sizeof(struct coda_cache) * coda_nc_size)
126 1.3 rvb #define TOTAL_HASH_SIZE (sizeof(struct coda_hash) * coda_nc_hashsize)
127 1.1 rvb
128 1.3 rvb int coda_nc_initialized = 0; /* Initially the cache has not been initialized */
129 1.1 rvb
130 1.1 rvb void
131 1.3 rvb coda_nc_init(void)
132 1.1 rvb {
133 1.1 rvb int i;
134 1.1 rvb
135 1.1 rvb /* zero the statistics structure */
136 1.14 perry
137 1.10 thorpej memset(&coda_nc_stat, 0, (sizeof(struct coda_nc_statistics)));
138 1.1 rvb
139 1.7 rvb #ifdef CODA_VERBOSE
140 1.3 rvb printf("CODA NAME CACHE: CACHE %d, HASH TBL %d\n", CODA_NC_CACHESIZE, CODA_NC_HASHSIZE);
141 1.5 rvb #endif
142 1.3 rvb CODA_ALLOC(coda_nc_heap, struct coda_cache *, TOTAL_CACHE_SIZE);
143 1.3 rvb CODA_ALLOC(coda_nc_hash, struct coda_hash *, TOTAL_HASH_SIZE);
144 1.14 perry
145 1.22 plunky memset(coda_nc_heap, 0, TOTAL_CACHE_SIZE);
146 1.22 plunky memset(coda_nc_hash, 0, TOTAL_HASH_SIZE);
147 1.14 perry
148 1.22 plunky TAILQ_INIT(&coda_nc_lru.head);
149 1.14 perry
150 1.3 rvb for (i=0; i < coda_nc_size; i++) { /* initialize the heap */
151 1.22 plunky TAILQ_INSERT_HEAD(&coda_nc_lru.head, &coda_nc_heap[i], lru);
152 1.1 rvb }
153 1.14 perry
154 1.3 rvb for (i=0; i < coda_nc_hashsize; i++) { /* initialize the hashtable */
155 1.22 plunky LIST_INIT(&coda_nc_hash[i].head);
156 1.1 rvb }
157 1.14 perry
158 1.3 rvb coda_nc_initialized++;
159 1.1 rvb }
160 1.1 rvb
161 1.1 rvb /*
162 1.28 andvar * Auxiliary routines -- shouldn't be entry points
163 1.1 rvb */
164 1.1 rvb
165 1.3 rvb static struct coda_cache *
166 1.16 xtraeme coda_nc_find(struct cnode *dcp, const char *name, int namelen,
167 1.18 elad kauth_cred_t cred, int hash)
168 1.1 rvb {
169 1.14 perry /*
170 1.1 rvb * hash to find the appropriate bucket, look through the chain
171 1.14 perry * for the right entry (especially right cred, unless cred == 0)
172 1.1 rvb */
173 1.3 rvb struct coda_cache *cncp;
174 1.1 rvb int count = 1;
175 1.1 rvb
176 1.14 perry CODA_NC_DEBUG(CODA_NC_FIND,
177 1.13 drochner myprintf(("coda_nc_find(dcp %p, name %s, len %d, cred %p, hash %d\n",
178 1.13 drochner dcp, name, namelen, cred, hash));)
179 1.1 rvb
180 1.22 plunky LIST_FOREACH(cncp, &coda_nc_hash[hash].head, hash)
181 1.1 rvb {
182 1.1 rvb
183 1.3 rvb if ((CODA_NAMEMATCH(cncp, name, namelen, dcp)) &&
184 1.14 perry ((cred == 0) || (cncp->cred == cred)))
185 1.14 perry {
186 1.1 rvb /* compare cr_uid instead */
187 1.3 rvb coda_nc_stat.Search_len += count;
188 1.1 rvb return(cncp);
189 1.1 rvb }
190 1.1 rvb #ifdef DEBUG
191 1.3 rvb else if (CODA_NAMEMATCH(cncp, name, namelen, dcp)) {
192 1.3 rvb printf("coda_nc_find: name %s, new cred = %p, cred = %p\n",
193 1.1 rvb name, cred, cncp->cred);
194 1.1 rvb printf("nref %d, nuid %d, ngid %d // oref %d, ocred %d, ogid %d\n",
195 1.18 elad kauth_cred_getrefcnt(cred),
196 1.18 elad kauth_cred_geteuid(cred),
197 1.18 elad kauth_cred_getegid(cred),
198 1.18 elad kauth_cred_getrefcnt(cncp->cred),
199 1.18 elad kauth_cred_geteuid(cncp->cred),
200 1.18 elad kauth_cred_getegid(cncp->cred));
201 1.25 christos coda_print_cred(cred);
202 1.25 christos coda_print_cred(cncp->cred);
203 1.1 rvb }
204 1.1 rvb #endif
205 1.22 plunky count++;
206 1.1 rvb }
207 1.1 rvb
208 1.3 rvb return((struct coda_cache *)0);
209 1.1 rvb }
210 1.1 rvb
211 1.1 rvb /*
212 1.1 rvb * Enter a new (dir cnode, name) pair into the cache, updating the
213 1.1 rvb * LRU and Hash as needed.
214 1.1 rvb */
215 1.1 rvb void
216 1.16 xtraeme coda_nc_enter(struct cnode *dcp, const char *name, int namelen,
217 1.18 elad kauth_cred_t cred, struct cnode *cp)
218 1.1 rvb {
219 1.3 rvb struct coda_cache *cncp;
220 1.1 rvb int hash;
221 1.14 perry
222 1.3 rvb if (coda_nc_use == 0) /* Cache is off */
223 1.1 rvb return;
224 1.14 perry
225 1.14 perry CODA_NC_DEBUG(CODA_NC_ENTER,
226 1.1 rvb myprintf(("Enter: dcp %p cp %p name %s cred %p \n",
227 1.1 rvb dcp, cp, name, cred)); )
228 1.14 perry
229 1.3 rvb if (namelen > CODA_NC_NAMELEN) {
230 1.14 perry CODA_NC_DEBUG(CODA_NC_ENTER,
231 1.1 rvb myprintf(("long name enter %s\n",name));)
232 1.3 rvb coda_nc_stat.long_name_enters++; /* record stats */
233 1.1 rvb return;
234 1.1 rvb }
235 1.14 perry
236 1.3 rvb hash = CODA_NC_HASH(name, namelen, dcp);
237 1.3 rvb cncp = coda_nc_find(dcp, name, namelen, cred, hash);
238 1.14 perry if (cncp != (struct coda_cache *) 0) {
239 1.3 rvb coda_nc_stat.dbl_enters++; /* duplicate entry */
240 1.1 rvb return;
241 1.1 rvb }
242 1.14 perry
243 1.3 rvb coda_nc_stat.enters++; /* record the enters statistic */
244 1.14 perry
245 1.1 rvb /* Grab the next element in the lru chain */
246 1.22 plunky cncp = TAILQ_FIRST(&coda_nc_lru.head);
247 1.22 plunky TAILQ_REMOVE(&coda_nc_lru.head, cncp, lru);
248 1.14 perry
249 1.3 rvb if (CODA_NC_VALID(cncp)) {
250 1.1 rvb /* Seems really ugly, but we have to decrement the appropriate
251 1.1 rvb hash bucket length here, so we have to find the hash bucket
252 1.1 rvb */
253 1.3 rvb coda_nc_hash[CODA_NC_HASH(cncp->name, cncp->namelen, cncp->dcp)].length--;
254 1.14 perry
255 1.3 rvb coda_nc_stat.lru_rm++; /* zapped a valid entry */
256 1.22 plunky LIST_REMOVE(cncp, hash);
257 1.14 perry vrele(CTOV(cncp->dcp));
258 1.1 rvb vrele(CTOV(cncp->cp));
259 1.18 elad kauth_cred_free(cncp->cred);
260 1.1 rvb }
261 1.14 perry
262 1.1 rvb /*
263 1.1 rvb * Put a hold on the current vnodes and fill in the cache entry.
264 1.1 rvb */
265 1.1 rvb vref(CTOV(cp));
266 1.1 rvb vref(CTOV(dcp));
267 1.18 elad kauth_cred_hold(cred);
268 1.1 rvb cncp->dcp = dcp;
269 1.1 rvb cncp->cp = cp;
270 1.1 rvb cncp->namelen = namelen;
271 1.1 rvb cncp->cred = cred;
272 1.14 perry
273 1.24 tsutsui memcpy(cncp->name, name, (unsigned)namelen);
274 1.14 perry
275 1.1 rvb /* Insert into the lru and hash chains. */
276 1.22 plunky TAILQ_INSERT_TAIL(&coda_nc_lru.head, cncp, lru);
277 1.22 plunky LIST_INSERT_HEAD(&coda_nc_hash[hash].head, cncp, hash);
278 1.3 rvb coda_nc_hash[hash].length++; /* Used for tuning */
279 1.14 perry
280 1.3 rvb CODA_NC_DEBUG(CODA_NC_PRINTCODA_NC, print_coda_nc(); )
281 1.1 rvb }
282 1.1 rvb
283 1.1 rvb /*
284 1.26 snj * Find the (dir cnode, name) pair in the cache, if its cred
285 1.1 rvb * matches the input, return it, otherwise return 0
286 1.1 rvb */
287 1.1 rvb struct cnode *
288 1.16 xtraeme coda_nc_lookup(struct cnode *dcp, const char *name, int namelen,
289 1.18 elad kauth_cred_t cred)
290 1.1 rvb {
291 1.1 rvb int hash;
292 1.3 rvb struct coda_cache *cncp;
293 1.1 rvb
294 1.3 rvb if (coda_nc_use == 0) /* Cache is off */
295 1.1 rvb return((struct cnode *) 0);
296 1.1 rvb
297 1.3 rvb if (namelen > CODA_NC_NAMELEN) {
298 1.14 perry CODA_NC_DEBUG(CODA_NC_LOOKUP,
299 1.1 rvb myprintf(("long name lookup %s\n",name));)
300 1.3 rvb coda_nc_stat.long_name_lookups++; /* record stats */
301 1.1 rvb return((struct cnode *) 0);
302 1.1 rvb }
303 1.1 rvb
304 1.1 rvb /* Use the hash function to locate the starting point,
305 1.1 rvb then the search routine to go down the list looking for
306 1.1 rvb the correct cred.
307 1.1 rvb */
308 1.1 rvb
309 1.3 rvb hash = CODA_NC_HASH(name, namelen, dcp);
310 1.3 rvb cncp = coda_nc_find(dcp, name, namelen, cred, hash);
311 1.3 rvb if (cncp == (struct coda_cache *) 0) {
312 1.3 rvb coda_nc_stat.misses++; /* record miss */
313 1.1 rvb return((struct cnode *) 0);
314 1.1 rvb }
315 1.1 rvb
316 1.3 rvb coda_nc_stat.hits++;
317 1.1 rvb
318 1.1 rvb /* put this entry at the end of the LRU */
319 1.22 plunky TAILQ_REMOVE(&coda_nc_lru.head, cncp, lru);
320 1.22 plunky TAILQ_INSERT_TAIL(&coda_nc_lru.head, cncp, lru);
321 1.1 rvb
322 1.1 rvb /* move it to the front of the hash chain */
323 1.1 rvb /* don't need to change the hash bucket length */
324 1.22 plunky LIST_REMOVE(cncp, hash);
325 1.22 plunky LIST_INSERT_HEAD(&coda_nc_hash[hash].head, cncp, hash);
326 1.1 rvb
327 1.14 perry CODA_NC_DEBUG(CODA_NC_LOOKUP,
328 1.1 rvb printf("lookup: dcp %p, name %s, cred %p = cp %p\n",
329 1.1 rvb dcp, name, cred, cncp->cp); )
330 1.1 rvb
331 1.1 rvb return(cncp->cp);
332 1.1 rvb }
333 1.1 rvb
334 1.1 rvb static void
335 1.16 xtraeme coda_nc_remove(struct coda_cache *cncp, enum dc_status dcstat)
336 1.1 rvb {
337 1.14 perry /*
338 1.1 rvb * remove an entry -- vrele(cncp->dcp, cp), crfree(cred),
339 1.26 snj * remove it from its hash chain, and
340 1.1 rvb * place it at the head of the lru list.
341 1.1 rvb */
342 1.3 rvb CODA_NC_DEBUG(CODA_NC_REMOVE,
343 1.13 drochner myprintf(("coda_nc_remove %s from parent %s\n",
344 1.13 drochner cncp->name, coda_f2s(&cncp->dcp->c_fid))); )
345 1.14 perry
346 1.1 rvb
347 1.22 plunky LIST_REMOVE(cncp, hash);
348 1.22 plunky memset(&cncp->hash, 0, sizeof(cncp->hash));
349 1.1 rvb
350 1.27 ad if ((dcstat == IS_DOWNCALL) && (vrefcnt(CTOV(cncp->dcp)) == 1)) {
351 1.1 rvb cncp->dcp->c_flags |= C_PURGING;
352 1.1 rvb }
353 1.14 perry vrele(CTOV(cncp->dcp));
354 1.1 rvb
355 1.27 ad if ((dcstat == IS_DOWNCALL) && (vrefcnt(CTOV(cncp->cp)) == 1)) {
356 1.1 rvb cncp->cp->c_flags |= C_PURGING;
357 1.1 rvb }
358 1.14 perry vrele(CTOV(cncp->cp));
359 1.1 rvb
360 1.18 elad kauth_cred_free(cncp->cred);
361 1.10 thorpej memset(DATA_PART(cncp), 0, DATA_SIZE);
362 1.1 rvb
363 1.22 plunky /* move the null entry to the front for reuse */
364 1.22 plunky TAILQ_REMOVE(&coda_nc_lru.head, cncp, lru);
365 1.22 plunky TAILQ_INSERT_HEAD(&coda_nc_lru.head, cncp, lru);
366 1.1 rvb }
367 1.1 rvb
368 1.1 rvb /*
369 1.1 rvb * Remove all entries with a parent which has the input fid.
370 1.1 rvb */
371 1.1 rvb void
372 1.16 xtraeme coda_nc_zapParentfid(CodaFid *fid, enum dc_status dcstat)
373 1.1 rvb {
374 1.1 rvb /* To get to a specific fid, we might either have another hashing
375 1.1 rvb function or do a sequential search through the cache for the
376 1.1 rvb appropriate entries. The later may be acceptable since I don't
377 1.12 wiz think callbacks or whatever Case 1 covers are frequent occurrences.
378 1.1 rvb */
379 1.3 rvb struct coda_cache *cncp, *ncncp;
380 1.1 rvb int i;
381 1.1 rvb
382 1.3 rvb if (coda_nc_use == 0) /* Cache is off */
383 1.1 rvb return;
384 1.1 rvb
385 1.14 perry CODA_NC_DEBUG(CODA_NC_ZAPPFID,
386 1.13 drochner myprintf(("ZapParent: fid %s\n", coda_f2s(fid))); )
387 1.1 rvb
388 1.3 rvb coda_nc_stat.zapPfids++;
389 1.1 rvb
390 1.3 rvb for (i = 0; i < coda_nc_hashsize; i++) {
391 1.1 rvb
392 1.1 rvb /*
393 1.1 rvb * Need to save the hash_next pointer in case we remove the
394 1.1 rvb * entry. remove causes hash_next to point to itself.
395 1.1 rvb */
396 1.1 rvb
397 1.22 plunky ncncp = LIST_FIRST(&coda_nc_hash[i].head);
398 1.22 plunky while ((cncp = ncncp) != NULL) {
399 1.22 plunky ncncp = LIST_NEXT(cncp, hash);
400 1.22 plunky
401 1.13 drochner if (coda_fid_eq(&(cncp->dcp->c_fid), fid)) {
402 1.3 rvb coda_nc_hash[i].length--; /* Used for tuning */
403 1.14 perry coda_nc_remove(cncp, dcstat);
404 1.1 rvb }
405 1.1 rvb }
406 1.1 rvb }
407 1.1 rvb }
408 1.1 rvb
409 1.1 rvb /*
410 1.1 rvb * Remove all entries which have the same fid as the input
411 1.1 rvb */
412 1.1 rvb void
413 1.16 xtraeme coda_nc_zapfid(CodaFid *fid, enum dc_status dcstat)
414 1.1 rvb {
415 1.1 rvb /* See comment for zapParentfid. This routine will be used
416 1.14 perry if attributes are being cached.
417 1.1 rvb */
418 1.3 rvb struct coda_cache *cncp, *ncncp;
419 1.1 rvb int i;
420 1.1 rvb
421 1.3 rvb if (coda_nc_use == 0) /* Cache is off */
422 1.1 rvb return;
423 1.1 rvb
424 1.14 perry CODA_NC_DEBUG(CODA_NC_ZAPFID,
425 1.13 drochner myprintf(("Zapfid: fid %s\n", coda_f2s(fid))); )
426 1.1 rvb
427 1.3 rvb coda_nc_stat.zapFids++;
428 1.1 rvb
429 1.3 rvb for (i = 0; i < coda_nc_hashsize; i++) {
430 1.22 plunky
431 1.22 plunky ncncp = LIST_FIRST(&coda_nc_hash[i].head);
432 1.22 plunky while ((cncp = ncncp) != NULL) {
433 1.22 plunky ncncp = LIST_NEXT(cncp, hash);
434 1.22 plunky
435 1.13 drochner if (coda_fid_eq(&cncp->cp->c_fid, fid)) {
436 1.3 rvb coda_nc_hash[i].length--; /* Used for tuning */
437 1.14 perry coda_nc_remove(cncp, dcstat);
438 1.1 rvb }
439 1.1 rvb }
440 1.1 rvb }
441 1.1 rvb }
442 1.1 rvb
443 1.14 perry /*
444 1.1 rvb * Remove all entries which match the fid and the cred
445 1.1 rvb */
446 1.1 rvb void
447 1.19 christos coda_nc_zapvnode(CodaFid *fid, kauth_cred_t cred,
448 1.20 christos enum dc_status dcstat)
449 1.1 rvb {
450 1.1 rvb /* See comment for zapfid. I don't think that one would ever
451 1.1 rvb want to zap a file with a specific cred from the kernel.
452 1.1 rvb We'll leave this one unimplemented.
453 1.1 rvb */
454 1.3 rvb if (coda_nc_use == 0) /* Cache is off */
455 1.1 rvb return;
456 1.1 rvb
457 1.14 perry CODA_NC_DEBUG(CODA_NC_ZAPVNODE,
458 1.13 drochner myprintf(("Zapvnode: fid %s cred %p\n",
459 1.13 drochner coda_f2s(fid), cred)); )
460 1.1 rvb }
461 1.1 rvb
462 1.1 rvb /*
463 1.1 rvb * Remove all entries which have the (dir vnode, name) pair
464 1.1 rvb */
465 1.1 rvb void
466 1.16 xtraeme coda_nc_zapfile(struct cnode *dcp, const char *name, int namelen)
467 1.1 rvb {
468 1.1 rvb /* use the hash function to locate the file, then zap all
469 1.1 rvb entries of it regardless of the cred.
470 1.1 rvb */
471 1.3 rvb struct coda_cache *cncp;
472 1.1 rvb int hash;
473 1.1 rvb
474 1.3 rvb if (coda_nc_use == 0) /* Cache is off */
475 1.1 rvb return;
476 1.1 rvb
477 1.14 perry CODA_NC_DEBUG(CODA_NC_ZAPFILE,
478 1.1 rvb myprintf(("Zapfile: dcp %p name %s \n",
479 1.1 rvb dcp, name)); )
480 1.1 rvb
481 1.3 rvb if (namelen > CODA_NC_NAMELEN) {
482 1.3 rvb coda_nc_stat.long_remove++; /* record stats */
483 1.1 rvb return;
484 1.1 rvb }
485 1.1 rvb
486 1.3 rvb coda_nc_stat.zapFile++;
487 1.1 rvb
488 1.3 rvb hash = CODA_NC_HASH(name, namelen, dcp);
489 1.3 rvb cncp = coda_nc_find(dcp, name, namelen, 0, hash);
490 1.1 rvb
491 1.1 rvb while (cncp) {
492 1.3 rvb coda_nc_hash[hash].length--; /* Used for tuning */
493 1.1 rvb /* 1.3 */
494 1.3 rvb coda_nc_remove(cncp, NOT_DOWNCALL);
495 1.3 rvb cncp = coda_nc_find(dcp, name, namelen, 0, hash);
496 1.1 rvb }
497 1.1 rvb }
498 1.1 rvb
499 1.14 perry /*
500 1.1 rvb * Remove all the entries for a particular user. Used when tokens expire.
501 1.1 rvb * A user is determined by his/her effective user id (id_uid).
502 1.1 rvb */
503 1.1 rvb void
504 1.16 xtraeme coda_nc_purge_user(uid_t uid, enum dc_status dcstat)
505 1.1 rvb {
506 1.14 perry /*
507 1.1 rvb * I think the best approach is to go through the entire cache
508 1.1 rvb * via HASH or whatever and zap all entries which match the
509 1.1 rvb * input cred. Or just flush the whole cache. It might be
510 1.1 rvb * best to go through on basis of LRU since cache will almost
511 1.14 perry * always be full and LRU is more straightforward.
512 1.1 rvb */
513 1.1 rvb
514 1.3 rvb struct coda_cache *cncp, *ncncp;
515 1.1 rvb int hash;
516 1.1 rvb
517 1.3 rvb if (coda_nc_use == 0) /* Cache is off */
518 1.1 rvb return;
519 1.1 rvb
520 1.14 perry CODA_NC_DEBUG(CODA_NC_PURGEUSER,
521 1.8 rvb myprintf(("ZapDude: uid %x\n", uid)); )
522 1.3 rvb coda_nc_stat.zapUsers++;
523 1.1 rvb
524 1.22 plunky ncncp = TAILQ_FIRST(&coda_nc_lru.head);
525 1.22 plunky while ((cncp = ncncp) != NULL) {
526 1.22 plunky ncncp = TAILQ_NEXT(cncp, lru);
527 1.1 rvb
528 1.3 rvb if ((CODA_NC_VALID(cncp)) &&
529 1.18 elad (kauth_cred_geteuid(cncp->cred) == uid)) {
530 1.1 rvb /* Seems really ugly, but we have to decrement the appropriate
531 1.1 rvb hash bucket length here, so we have to find the hash bucket
532 1.1 rvb */
533 1.3 rvb hash = CODA_NC_HASH(cncp->name, cncp->namelen, cncp->dcp);
534 1.3 rvb coda_nc_hash[hash].length--; /* For performance tuning */
535 1.1 rvb
536 1.14 perry coda_nc_remove(cncp, dcstat);
537 1.1 rvb }
538 1.1 rvb }
539 1.1 rvb }
540 1.1 rvb
541 1.1 rvb /*
542 1.1 rvb * Flush the entire name cache. In response to a flush of the Venus cache.
543 1.1 rvb */
544 1.1 rvb void
545 1.16 xtraeme coda_nc_flush(enum dc_status dcstat)
546 1.1 rvb {
547 1.1 rvb /* One option is to deallocate the current name cache and
548 1.1 rvb call init to start again. Or just deallocate, then rebuild.
549 1.14 perry Or again, we could just go through the array and zero the
550 1.14 perry appropriate fields.
551 1.1 rvb */
552 1.14 perry
553 1.14 perry /*
554 1.1 rvb * Go through the whole lru chain and kill everything as we go.
555 1.1 rvb * I don't use remove since that would rebuild the lru chain
556 1.29 andvar * as it went and that seemed unnecessary.
557 1.1 rvb */
558 1.3 rvb struct coda_cache *cncp;
559 1.1 rvb int i;
560 1.1 rvb
561 1.3 rvb if (coda_nc_use == 0) /* Cache is off */
562 1.1 rvb return;
563 1.1 rvb
564 1.3 rvb coda_nc_stat.Flushes++;
565 1.1 rvb
566 1.22 plunky TAILQ_FOREACH(cncp, &coda_nc_lru.head, lru) {
567 1.22 plunky if (CODA_NC_VALID(cncp)) { /* only zero valid nodes */
568 1.22 plunky LIST_REMOVE(cncp, hash);
569 1.22 plunky memset(&cncp->hash, 0, sizeof(cncp->hash));
570 1.1 rvb
571 1.14 perry if ((dcstat == IS_DOWNCALL)
572 1.27 ad && (vrefcnt(CTOV(cncp->dcp)) == 1))
573 1.1 rvb {
574 1.1 rvb cncp->dcp->c_flags |= C_PURGING;
575 1.1 rvb }
576 1.14 perry vrele(CTOV(cncp->dcp));
577 1.1 rvb
578 1.21 ad if (CTOV(cncp->cp)->v_iflag & VI_TEXT) {
579 1.3 rvb if (coda_vmflush(cncp->cp))
580 1.14 perry CODADEBUG(CODA_FLUSH,
581 1.13 drochner myprintf(("coda_nc_flush: %s busy\n",
582 1.13 drochner coda_f2s(&cncp->cp->c_fid))); )
583 1.1 rvb }
584 1.1 rvb
585 1.14 perry if ((dcstat == IS_DOWNCALL)
586 1.27 ad && (vrefcnt(CTOV(cncp->cp)) == 1))
587 1.1 rvb {
588 1.1 rvb cncp->cp->c_flags |= C_PURGING;
589 1.1 rvb }
590 1.14 perry vrele(CTOV(cncp->cp));
591 1.1 rvb
592 1.18 elad kauth_cred_free(cncp->cred);
593 1.10 thorpej memset(DATA_PART(cncp), 0, DATA_SIZE);
594 1.1 rvb }
595 1.1 rvb }
596 1.1 rvb
597 1.3 rvb for (i = 0; i < coda_nc_hashsize; i++)
598 1.3 rvb coda_nc_hash[i].length = 0;
599 1.1 rvb }
600 1.1 rvb
601 1.1 rvb /*
602 1.1 rvb * Debugging routines
603 1.1 rvb */
604 1.1 rvb
605 1.14 perry /*
606 1.1 rvb * This routine should print out all the hash chains to the console.
607 1.1 rvb */
608 1.1 rvb void
609 1.3 rvb print_coda_nc(void)
610 1.1 rvb {
611 1.1 rvb int hash;
612 1.3 rvb struct coda_cache *cncp;
613 1.1 rvb
614 1.3 rvb for (hash = 0; hash < coda_nc_hashsize; hash++) {
615 1.1 rvb myprintf(("\nhash %d\n",hash));
616 1.1 rvb
617 1.22 plunky LIST_FOREACH(cncp, &coda_nc_hash[hash].head, hash) {
618 1.1 rvb myprintf(("cp %p dcp %p cred %p name %s\n",
619 1.1 rvb cncp->cp, cncp->dcp,
620 1.1 rvb cncp->cred, cncp->name));
621 1.1 rvb }
622 1.1 rvb }
623 1.1 rvb }
624 1.1 rvb
625 1.1 rvb void
626 1.3 rvb coda_nc_gather_stats(void)
627 1.1 rvb {
628 1.15 christos int i, xmax = 0, sum = 0, temp, zeros = 0, ave, n;
629 1.1 rvb
630 1.3 rvb for (i = 0; i < coda_nc_hashsize; i++) {
631 1.3 rvb if (coda_nc_hash[i].length) {
632 1.3 rvb sum += coda_nc_hash[i].length;
633 1.1 rvb } else {
634 1.1 rvb zeros++;
635 1.1 rvb }
636 1.1 rvb
637 1.15 christos if (coda_nc_hash[i].length > xmax)
638 1.15 christos xmax = coda_nc_hash[i].length;
639 1.1 rvb }
640 1.1 rvb
641 1.1 rvb /*
642 1.14 perry * When computing the Arithmetic mean, only count slots which
643 1.1 rvb * are not empty in the distribution.
644 1.1 rvb */
645 1.3 rvb coda_nc_stat.Sum_bucket_len = sum;
646 1.3 rvb coda_nc_stat.Num_zero_len = zeros;
647 1.15 christos coda_nc_stat.Max_bucket_len = xmax;
648 1.1 rvb
649 1.14 perry if ((n = coda_nc_hashsize - zeros) > 0)
650 1.1 rvb ave = sum / n;
651 1.1 rvb else
652 1.1 rvb ave = 0;
653 1.1 rvb
654 1.1 rvb sum = 0;
655 1.3 rvb for (i = 0; i < coda_nc_hashsize; i++) {
656 1.3 rvb if (coda_nc_hash[i].length) {
657 1.3 rvb temp = coda_nc_hash[i].length - ave;
658 1.1 rvb sum += temp * temp;
659 1.1 rvb }
660 1.1 rvb }
661 1.3 rvb coda_nc_stat.Sum2_bucket_len = sum;
662 1.1 rvb }
663 1.1 rvb
664 1.1 rvb /*
665 1.1 rvb * The purpose of this routine is to allow the hash and cache sizes to be
666 1.1 rvb * changed dynamically. This should only be used in controlled environments,
667 1.1 rvb * it makes no effort to lock other users from accessing the cache while it
668 1.1 rvb * is in an improper state (except by turning the cache off).
669 1.1 rvb */
670 1.1 rvb int
671 1.16 xtraeme coda_nc_resize(int hashsize, int heapsize, enum dc_status dcstat)
672 1.1 rvb {
673 1.1 rvb if ((hashsize % 2) || (heapsize % 2)) { /* Illegal hash or cache sizes */
674 1.1 rvb return(EINVAL);
675 1.14 perry }
676 1.14 perry
677 1.3 rvb coda_nc_use = 0; /* Turn the cache off */
678 1.14 perry
679 1.3 rvb coda_nc_flush(dcstat); /* free any cnodes in the cache */
680 1.14 perry
681 1.1 rvb /* WARNING: free must happen *before* size is reset */
682 1.3 rvb CODA_FREE(coda_nc_heap,TOTAL_CACHE_SIZE);
683 1.3 rvb CODA_FREE(coda_nc_hash,TOTAL_HASH_SIZE);
684 1.14 perry
685 1.3 rvb coda_nc_hashsize = hashsize;
686 1.3 rvb coda_nc_size = heapsize;
687 1.14 perry
688 1.3 rvb coda_nc_init(); /* Set up a cache with the new size */
689 1.14 perry
690 1.3 rvb coda_nc_use = 1; /* Turn the cache back on */
691 1.1 rvb return(0);
692 1.1 rvb }
693 1.1 rvb
694 1.3 rvb char coda_nc_name_buf[CODA_MAXNAMLEN+1];
695 1.1 rvb
696 1.1 rvb void
697 1.3 rvb coda_nc_name(struct cnode *cp)
698 1.1 rvb {
699 1.22 plunky struct coda_cache *cncp;
700 1.1 rvb int i;
701 1.1 rvb
702 1.3 rvb if (coda_nc_use == 0) /* Cache is off */
703 1.1 rvb return;
704 1.1 rvb
705 1.3 rvb for (i = 0; i < coda_nc_hashsize; i++) {
706 1.22 plunky
707 1.22 plunky LIST_FOREACH(cncp, &coda_nc_hash[i].head, hash) {
708 1.1 rvb if (cncp->cp == cp) {
709 1.24 tsutsui memcpy(coda_nc_name_buf, cncp->name, cncp->namelen);
710 1.3 rvb coda_nc_name_buf[cncp->namelen] = 0;
711 1.1 rvb printf(" is %s (%p,%p)@%p",
712 1.3 rvb coda_nc_name_buf, cncp->cp, cncp->dcp, cncp);
713 1.1 rvb }
714 1.1 rvb
715 1.1 rvb }
716 1.1 rvb }
717 1.1 rvb }
718