coda_namecache.c revision 1.26 1 1.26 snj /* $NetBSD: coda_namecache.c,v 1.26 2014/10/18 08:33:27 snj 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 1.26 snj __KERNEL_RCSID(0, "$NetBSD: coda_namecache.c,v 1.26 2014/10/18 08:33:27 snj 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/malloc.h>
85 1.1 rvb #include <sys/select.h>
86 1.18 elad #include <sys/kauth.h>
87 1.1 rvb
88 1.4 rvb #include <coda/coda.h>
89 1.4 rvb #include <coda/cnode.h>
90 1.4 rvb #include <coda/coda_namecache.h>
91 1.25 christos #include <coda/coda_subr.h>
92 1.5 rvb
93 1.14 perry /*
94 1.1 rvb * Declaration of the name cache data structure.
95 1.1 rvb */
96 1.1 rvb
97 1.3 rvb int coda_nc_use = 1; /* Indicate use of CODA Name Cache */
98 1.1 rvb
99 1.3 rvb int coda_nc_size = CODA_NC_CACHESIZE; /* size of the cache */
100 1.3 rvb int coda_nc_hashsize = CODA_NC_HASHSIZE; /* size of the primary hash */
101 1.1 rvb
102 1.3 rvb struct coda_cache *coda_nc_heap; /* pointer to the cache entries */
103 1.3 rvb struct coda_hash *coda_nc_hash; /* hash table of cfscache pointers */
104 1.3 rvb struct coda_lru coda_nc_lru; /* head of lru chain */
105 1.1 rvb
106 1.3 rvb struct coda_nc_statistics coda_nc_stat; /* Keep various stats */
107 1.1 rvb
108 1.14 perry /*
109 1.1 rvb * for testing purposes
110 1.1 rvb */
111 1.3 rvb int coda_nc_debug = 0;
112 1.1 rvb
113 1.1 rvb /*
114 1.3 rvb * Entry points for the CODA Name Cache
115 1.1 rvb */
116 1.3 rvb static struct coda_cache *
117 1.3 rvb coda_nc_find(struct cnode *dcp, const char *name, int namelen,
118 1.18 elad kauth_cred_t cred, int hash);
119 1.1 rvb static void
120 1.3 rvb coda_nc_remove(struct coda_cache *cncp, enum dc_status dcstat);
121 1.1 rvb
122 1.14 perry /*
123 1.1 rvb * Initialize the cache, the LRU structure and the Hash structure(s)
124 1.1 rvb */
125 1.1 rvb
126 1.3 rvb #define TOTAL_CACHE_SIZE (sizeof(struct coda_cache) * coda_nc_size)
127 1.3 rvb #define TOTAL_HASH_SIZE (sizeof(struct coda_hash) * coda_nc_hashsize)
128 1.1 rvb
129 1.3 rvb int coda_nc_initialized = 0; /* Initially the cache has not been initialized */
130 1.1 rvb
131 1.1 rvb void
132 1.3 rvb coda_nc_init(void)
133 1.1 rvb {
134 1.1 rvb int i;
135 1.1 rvb
136 1.1 rvb /* zero the statistics structure */
137 1.14 perry
138 1.10 thorpej memset(&coda_nc_stat, 0, (sizeof(struct coda_nc_statistics)));
139 1.1 rvb
140 1.7 rvb #ifdef CODA_VERBOSE
141 1.3 rvb printf("CODA NAME CACHE: CACHE %d, HASH TBL %d\n", CODA_NC_CACHESIZE, CODA_NC_HASHSIZE);
142 1.5 rvb #endif
143 1.3 rvb CODA_ALLOC(coda_nc_heap, struct coda_cache *, TOTAL_CACHE_SIZE);
144 1.3 rvb CODA_ALLOC(coda_nc_hash, struct coda_hash *, TOTAL_HASH_SIZE);
145 1.14 perry
146 1.22 plunky memset(coda_nc_heap, 0, TOTAL_CACHE_SIZE);
147 1.22 plunky memset(coda_nc_hash, 0, TOTAL_HASH_SIZE);
148 1.14 perry
149 1.22 plunky TAILQ_INIT(&coda_nc_lru.head);
150 1.14 perry
151 1.3 rvb for (i=0; i < coda_nc_size; i++) { /* initialize the heap */
152 1.22 plunky TAILQ_INSERT_HEAD(&coda_nc_lru.head, &coda_nc_heap[i], lru);
153 1.1 rvb }
154 1.14 perry
155 1.3 rvb for (i=0; i < coda_nc_hashsize; i++) { /* initialize the hashtable */
156 1.22 plunky LIST_INIT(&coda_nc_hash[i].head);
157 1.1 rvb }
158 1.14 perry
159 1.3 rvb coda_nc_initialized++;
160 1.1 rvb }
161 1.1 rvb
162 1.1 rvb /*
163 1.1 rvb * Auxillary routines -- shouldn't be entry points
164 1.1 rvb */
165 1.1 rvb
166 1.3 rvb static struct coda_cache *
167 1.16 xtraeme coda_nc_find(struct cnode *dcp, const char *name, int namelen,
168 1.18 elad kauth_cred_t cred, int hash)
169 1.1 rvb {
170 1.14 perry /*
171 1.1 rvb * hash to find the appropriate bucket, look through the chain
172 1.14 perry * for the right entry (especially right cred, unless cred == 0)
173 1.1 rvb */
174 1.3 rvb struct coda_cache *cncp;
175 1.1 rvb int count = 1;
176 1.1 rvb
177 1.14 perry CODA_NC_DEBUG(CODA_NC_FIND,
178 1.13 drochner myprintf(("coda_nc_find(dcp %p, name %s, len %d, cred %p, hash %d\n",
179 1.13 drochner dcp, name, namelen, cred, hash));)
180 1.1 rvb
181 1.22 plunky LIST_FOREACH(cncp, &coda_nc_hash[hash].head, hash)
182 1.1 rvb {
183 1.1 rvb
184 1.3 rvb if ((CODA_NAMEMATCH(cncp, name, namelen, dcp)) &&
185 1.14 perry ((cred == 0) || (cncp->cred == cred)))
186 1.14 perry {
187 1.1 rvb /* compare cr_uid instead */
188 1.3 rvb coda_nc_stat.Search_len += count;
189 1.1 rvb return(cncp);
190 1.1 rvb }
191 1.1 rvb #ifdef DEBUG
192 1.3 rvb else if (CODA_NAMEMATCH(cncp, name, namelen, dcp)) {
193 1.3 rvb printf("coda_nc_find: name %s, new cred = %p, cred = %p\n",
194 1.1 rvb name, cred, cncp->cred);
195 1.1 rvb printf("nref %d, nuid %d, ngid %d // oref %d, ocred %d, ogid %d\n",
196 1.18 elad kauth_cred_getrefcnt(cred),
197 1.18 elad kauth_cred_geteuid(cred),
198 1.18 elad kauth_cred_getegid(cred),
199 1.18 elad kauth_cred_getrefcnt(cncp->cred),
200 1.18 elad kauth_cred_geteuid(cncp->cred),
201 1.18 elad kauth_cred_getegid(cncp->cred));
202 1.25 christos coda_print_cred(cred);
203 1.25 christos coda_print_cred(cncp->cred);
204 1.1 rvb }
205 1.1 rvb #endif
206 1.22 plunky count++;
207 1.1 rvb }
208 1.1 rvb
209 1.3 rvb return((struct coda_cache *)0);
210 1.1 rvb }
211 1.1 rvb
212 1.1 rvb /*
213 1.1 rvb * Enter a new (dir cnode, name) pair into the cache, updating the
214 1.1 rvb * LRU and Hash as needed.
215 1.1 rvb */
216 1.1 rvb void
217 1.16 xtraeme coda_nc_enter(struct cnode *dcp, const char *name, int namelen,
218 1.18 elad kauth_cred_t cred, struct cnode *cp)
219 1.1 rvb {
220 1.3 rvb struct coda_cache *cncp;
221 1.1 rvb int hash;
222 1.14 perry
223 1.3 rvb if (coda_nc_use == 0) /* Cache is off */
224 1.1 rvb return;
225 1.14 perry
226 1.14 perry CODA_NC_DEBUG(CODA_NC_ENTER,
227 1.1 rvb myprintf(("Enter: dcp %p cp %p name %s cred %p \n",
228 1.1 rvb dcp, cp, name, cred)); )
229 1.14 perry
230 1.3 rvb if (namelen > CODA_NC_NAMELEN) {
231 1.14 perry CODA_NC_DEBUG(CODA_NC_ENTER,
232 1.1 rvb myprintf(("long name enter %s\n",name));)
233 1.3 rvb coda_nc_stat.long_name_enters++; /* record stats */
234 1.1 rvb return;
235 1.1 rvb }
236 1.14 perry
237 1.3 rvb hash = CODA_NC_HASH(name, namelen, dcp);
238 1.3 rvb cncp = coda_nc_find(dcp, name, namelen, cred, hash);
239 1.14 perry if (cncp != (struct coda_cache *) 0) {
240 1.3 rvb coda_nc_stat.dbl_enters++; /* duplicate entry */
241 1.1 rvb return;
242 1.1 rvb }
243 1.14 perry
244 1.3 rvb coda_nc_stat.enters++; /* record the enters statistic */
245 1.14 perry
246 1.1 rvb /* Grab the next element in the lru chain */
247 1.22 plunky cncp = TAILQ_FIRST(&coda_nc_lru.head);
248 1.22 plunky TAILQ_REMOVE(&coda_nc_lru.head, cncp, lru);
249 1.14 perry
250 1.3 rvb if (CODA_NC_VALID(cncp)) {
251 1.1 rvb /* Seems really ugly, but we have to decrement the appropriate
252 1.1 rvb hash bucket length here, so we have to find the hash bucket
253 1.1 rvb */
254 1.3 rvb coda_nc_hash[CODA_NC_HASH(cncp->name, cncp->namelen, cncp->dcp)].length--;
255 1.14 perry
256 1.3 rvb coda_nc_stat.lru_rm++; /* zapped a valid entry */
257 1.22 plunky LIST_REMOVE(cncp, hash);
258 1.14 perry vrele(CTOV(cncp->dcp));
259 1.1 rvb vrele(CTOV(cncp->cp));
260 1.18 elad kauth_cred_free(cncp->cred);
261 1.1 rvb }
262 1.14 perry
263 1.1 rvb /*
264 1.1 rvb * Put a hold on the current vnodes and fill in the cache entry.
265 1.1 rvb */
266 1.1 rvb vref(CTOV(cp));
267 1.1 rvb vref(CTOV(dcp));
268 1.18 elad kauth_cred_hold(cred);
269 1.1 rvb cncp->dcp = dcp;
270 1.1 rvb cncp->cp = cp;
271 1.1 rvb cncp->namelen = namelen;
272 1.1 rvb cncp->cred = cred;
273 1.14 perry
274 1.24 tsutsui memcpy(cncp->name, name, (unsigned)namelen);
275 1.14 perry
276 1.1 rvb /* Insert into the lru and hash chains. */
277 1.22 plunky TAILQ_INSERT_TAIL(&coda_nc_lru.head, cncp, lru);
278 1.22 plunky LIST_INSERT_HEAD(&coda_nc_hash[hash].head, cncp, hash);
279 1.3 rvb coda_nc_hash[hash].length++; /* Used for tuning */
280 1.14 perry
281 1.3 rvb CODA_NC_DEBUG(CODA_NC_PRINTCODA_NC, print_coda_nc(); )
282 1.1 rvb }
283 1.1 rvb
284 1.1 rvb /*
285 1.26 snj * Find the (dir cnode, name) pair in the cache, if its cred
286 1.1 rvb * matches the input, return it, otherwise return 0
287 1.1 rvb */
288 1.1 rvb struct cnode *
289 1.16 xtraeme coda_nc_lookup(struct cnode *dcp, const char *name, int namelen,
290 1.18 elad kauth_cred_t cred)
291 1.1 rvb {
292 1.1 rvb int hash;
293 1.3 rvb struct coda_cache *cncp;
294 1.1 rvb
295 1.3 rvb if (coda_nc_use == 0) /* Cache is off */
296 1.1 rvb return((struct cnode *) 0);
297 1.1 rvb
298 1.3 rvb if (namelen > CODA_NC_NAMELEN) {
299 1.14 perry CODA_NC_DEBUG(CODA_NC_LOOKUP,
300 1.1 rvb myprintf(("long name lookup %s\n",name));)
301 1.3 rvb coda_nc_stat.long_name_lookups++; /* record stats */
302 1.1 rvb return((struct cnode *) 0);
303 1.1 rvb }
304 1.1 rvb
305 1.1 rvb /* Use the hash function to locate the starting point,
306 1.1 rvb then the search routine to go down the list looking for
307 1.1 rvb the correct cred.
308 1.1 rvb */
309 1.1 rvb
310 1.3 rvb hash = CODA_NC_HASH(name, namelen, dcp);
311 1.3 rvb cncp = coda_nc_find(dcp, name, namelen, cred, hash);
312 1.3 rvb if (cncp == (struct coda_cache *) 0) {
313 1.3 rvb coda_nc_stat.misses++; /* record miss */
314 1.1 rvb return((struct cnode *) 0);
315 1.1 rvb }
316 1.1 rvb
317 1.3 rvb coda_nc_stat.hits++;
318 1.1 rvb
319 1.1 rvb /* put this entry at the end of the LRU */
320 1.22 plunky TAILQ_REMOVE(&coda_nc_lru.head, cncp, lru);
321 1.22 plunky TAILQ_INSERT_TAIL(&coda_nc_lru.head, cncp, lru);
322 1.1 rvb
323 1.1 rvb /* move it to the front of the hash chain */
324 1.1 rvb /* don't need to change the hash bucket length */
325 1.22 plunky LIST_REMOVE(cncp, hash);
326 1.22 plunky LIST_INSERT_HEAD(&coda_nc_hash[hash].head, cncp, hash);
327 1.1 rvb
328 1.14 perry CODA_NC_DEBUG(CODA_NC_LOOKUP,
329 1.1 rvb printf("lookup: dcp %p, name %s, cred %p = cp %p\n",
330 1.1 rvb dcp, name, cred, cncp->cp); )
331 1.1 rvb
332 1.1 rvb return(cncp->cp);
333 1.1 rvb }
334 1.1 rvb
335 1.1 rvb static void
336 1.16 xtraeme coda_nc_remove(struct coda_cache *cncp, enum dc_status dcstat)
337 1.1 rvb {
338 1.14 perry /*
339 1.1 rvb * remove an entry -- vrele(cncp->dcp, cp), crfree(cred),
340 1.26 snj * remove it from its hash chain, and
341 1.1 rvb * place it at the head of the lru list.
342 1.1 rvb */
343 1.3 rvb CODA_NC_DEBUG(CODA_NC_REMOVE,
344 1.13 drochner myprintf(("coda_nc_remove %s from parent %s\n",
345 1.13 drochner cncp->name, coda_f2s(&cncp->dcp->c_fid))); )
346 1.14 perry
347 1.1 rvb
348 1.22 plunky LIST_REMOVE(cncp, hash);
349 1.22 plunky memset(&cncp->hash, 0, sizeof(cncp->hash));
350 1.1 rvb
351 1.1 rvb if ((dcstat == IS_DOWNCALL) && (CTOV(cncp->dcp)->v_usecount == 1)) {
352 1.1 rvb cncp->dcp->c_flags |= C_PURGING;
353 1.1 rvb }
354 1.14 perry vrele(CTOV(cncp->dcp));
355 1.1 rvb
356 1.1 rvb if ((dcstat == IS_DOWNCALL) && (CTOV(cncp->cp)->v_usecount == 1)) {
357 1.1 rvb cncp->cp->c_flags |= C_PURGING;
358 1.1 rvb }
359 1.14 perry vrele(CTOV(cncp->cp));
360 1.1 rvb
361 1.18 elad kauth_cred_free(cncp->cred);
362 1.10 thorpej memset(DATA_PART(cncp), 0, DATA_SIZE);
363 1.1 rvb
364 1.22 plunky /* move the null entry to the front for reuse */
365 1.22 plunky TAILQ_REMOVE(&coda_nc_lru.head, cncp, lru);
366 1.22 plunky TAILQ_INSERT_HEAD(&coda_nc_lru.head, cncp, lru);
367 1.1 rvb }
368 1.1 rvb
369 1.1 rvb /*
370 1.1 rvb * Remove all entries with a parent which has the input fid.
371 1.1 rvb */
372 1.1 rvb void
373 1.16 xtraeme coda_nc_zapParentfid(CodaFid *fid, enum dc_status dcstat)
374 1.1 rvb {
375 1.1 rvb /* To get to a specific fid, we might either have another hashing
376 1.1 rvb function or do a sequential search through the cache for the
377 1.1 rvb appropriate entries. The later may be acceptable since I don't
378 1.12 wiz think callbacks or whatever Case 1 covers are frequent occurrences.
379 1.1 rvb */
380 1.3 rvb struct coda_cache *cncp, *ncncp;
381 1.1 rvb int i;
382 1.1 rvb
383 1.3 rvb if (coda_nc_use == 0) /* Cache is off */
384 1.1 rvb return;
385 1.1 rvb
386 1.14 perry CODA_NC_DEBUG(CODA_NC_ZAPPFID,
387 1.13 drochner myprintf(("ZapParent: fid %s\n", coda_f2s(fid))); )
388 1.1 rvb
389 1.3 rvb coda_nc_stat.zapPfids++;
390 1.1 rvb
391 1.3 rvb for (i = 0; i < coda_nc_hashsize; i++) {
392 1.1 rvb
393 1.1 rvb /*
394 1.1 rvb * Need to save the hash_next pointer in case we remove the
395 1.1 rvb * entry. remove causes hash_next to point to itself.
396 1.1 rvb */
397 1.1 rvb
398 1.22 plunky ncncp = LIST_FIRST(&coda_nc_hash[i].head);
399 1.22 plunky while ((cncp = ncncp) != NULL) {
400 1.22 plunky ncncp = LIST_NEXT(cncp, hash);
401 1.22 plunky
402 1.13 drochner if (coda_fid_eq(&(cncp->dcp->c_fid), fid)) {
403 1.3 rvb coda_nc_hash[i].length--; /* Used for tuning */
404 1.14 perry coda_nc_remove(cncp, dcstat);
405 1.1 rvb }
406 1.1 rvb }
407 1.1 rvb }
408 1.1 rvb }
409 1.1 rvb
410 1.1 rvb /*
411 1.1 rvb * Remove all entries which have the same fid as the input
412 1.1 rvb */
413 1.1 rvb void
414 1.16 xtraeme coda_nc_zapfid(CodaFid *fid, enum dc_status dcstat)
415 1.1 rvb {
416 1.1 rvb /* See comment for zapParentfid. This routine will be used
417 1.14 perry if attributes are being cached.
418 1.1 rvb */
419 1.3 rvb struct coda_cache *cncp, *ncncp;
420 1.1 rvb int i;
421 1.1 rvb
422 1.3 rvb if (coda_nc_use == 0) /* Cache is off */
423 1.1 rvb return;
424 1.1 rvb
425 1.14 perry CODA_NC_DEBUG(CODA_NC_ZAPFID,
426 1.13 drochner myprintf(("Zapfid: fid %s\n", coda_f2s(fid))); )
427 1.1 rvb
428 1.3 rvb coda_nc_stat.zapFids++;
429 1.1 rvb
430 1.3 rvb for (i = 0; i < coda_nc_hashsize; i++) {
431 1.22 plunky
432 1.22 plunky ncncp = LIST_FIRST(&coda_nc_hash[i].head);
433 1.22 plunky while ((cncp = ncncp) != NULL) {
434 1.22 plunky ncncp = LIST_NEXT(cncp, hash);
435 1.22 plunky
436 1.13 drochner if (coda_fid_eq(&cncp->cp->c_fid, fid)) {
437 1.3 rvb coda_nc_hash[i].length--; /* Used for tuning */
438 1.14 perry coda_nc_remove(cncp, dcstat);
439 1.1 rvb }
440 1.1 rvb }
441 1.1 rvb }
442 1.1 rvb }
443 1.1 rvb
444 1.14 perry /*
445 1.1 rvb * Remove all entries which match the fid and the cred
446 1.1 rvb */
447 1.1 rvb void
448 1.19 christos coda_nc_zapvnode(CodaFid *fid, kauth_cred_t cred,
449 1.20 christos enum dc_status dcstat)
450 1.1 rvb {
451 1.1 rvb /* See comment for zapfid. I don't think that one would ever
452 1.1 rvb want to zap a file with a specific cred from the kernel.
453 1.1 rvb We'll leave this one unimplemented.
454 1.1 rvb */
455 1.3 rvb if (coda_nc_use == 0) /* Cache is off */
456 1.1 rvb return;
457 1.1 rvb
458 1.14 perry CODA_NC_DEBUG(CODA_NC_ZAPVNODE,
459 1.13 drochner myprintf(("Zapvnode: fid %s cred %p\n",
460 1.13 drochner coda_f2s(fid), cred)); )
461 1.1 rvb }
462 1.1 rvb
463 1.1 rvb /*
464 1.1 rvb * Remove all entries which have the (dir vnode, name) pair
465 1.1 rvb */
466 1.1 rvb void
467 1.16 xtraeme coda_nc_zapfile(struct cnode *dcp, const char *name, int namelen)
468 1.1 rvb {
469 1.1 rvb /* use the hash function to locate the file, then zap all
470 1.1 rvb entries of it regardless of the cred.
471 1.1 rvb */
472 1.3 rvb struct coda_cache *cncp;
473 1.1 rvb int hash;
474 1.1 rvb
475 1.3 rvb if (coda_nc_use == 0) /* Cache is off */
476 1.1 rvb return;
477 1.1 rvb
478 1.14 perry CODA_NC_DEBUG(CODA_NC_ZAPFILE,
479 1.1 rvb myprintf(("Zapfile: dcp %p name %s \n",
480 1.1 rvb dcp, name)); )
481 1.1 rvb
482 1.3 rvb if (namelen > CODA_NC_NAMELEN) {
483 1.3 rvb coda_nc_stat.long_remove++; /* record stats */
484 1.1 rvb return;
485 1.1 rvb }
486 1.1 rvb
487 1.3 rvb coda_nc_stat.zapFile++;
488 1.1 rvb
489 1.3 rvb hash = CODA_NC_HASH(name, namelen, dcp);
490 1.3 rvb cncp = coda_nc_find(dcp, name, namelen, 0, hash);
491 1.1 rvb
492 1.1 rvb while (cncp) {
493 1.3 rvb coda_nc_hash[hash].length--; /* Used for tuning */
494 1.1 rvb /* 1.3 */
495 1.3 rvb coda_nc_remove(cncp, NOT_DOWNCALL);
496 1.3 rvb cncp = coda_nc_find(dcp, name, namelen, 0, hash);
497 1.1 rvb }
498 1.1 rvb }
499 1.1 rvb
500 1.14 perry /*
501 1.1 rvb * Remove all the entries for a particular user. Used when tokens expire.
502 1.1 rvb * A user is determined by his/her effective user id (id_uid).
503 1.1 rvb */
504 1.1 rvb void
505 1.16 xtraeme coda_nc_purge_user(uid_t uid, enum dc_status dcstat)
506 1.1 rvb {
507 1.14 perry /*
508 1.1 rvb * I think the best approach is to go through the entire cache
509 1.1 rvb * via HASH or whatever and zap all entries which match the
510 1.1 rvb * input cred. Or just flush the whole cache. It might be
511 1.1 rvb * best to go through on basis of LRU since cache will almost
512 1.14 perry * always be full and LRU is more straightforward.
513 1.1 rvb */
514 1.1 rvb
515 1.3 rvb struct coda_cache *cncp, *ncncp;
516 1.1 rvb int hash;
517 1.1 rvb
518 1.3 rvb if (coda_nc_use == 0) /* Cache is off */
519 1.1 rvb return;
520 1.1 rvb
521 1.14 perry CODA_NC_DEBUG(CODA_NC_PURGEUSER,
522 1.8 rvb myprintf(("ZapDude: uid %x\n", uid)); )
523 1.3 rvb coda_nc_stat.zapUsers++;
524 1.1 rvb
525 1.22 plunky ncncp = TAILQ_FIRST(&coda_nc_lru.head);
526 1.22 plunky while ((cncp = ncncp) != NULL) {
527 1.22 plunky ncncp = TAILQ_NEXT(cncp, lru);
528 1.1 rvb
529 1.3 rvb if ((CODA_NC_VALID(cncp)) &&
530 1.18 elad (kauth_cred_geteuid(cncp->cred) == uid)) {
531 1.1 rvb /* Seems really ugly, but we have to decrement the appropriate
532 1.1 rvb hash bucket length here, so we have to find the hash bucket
533 1.1 rvb */
534 1.3 rvb hash = CODA_NC_HASH(cncp->name, cncp->namelen, cncp->dcp);
535 1.3 rvb coda_nc_hash[hash].length--; /* For performance tuning */
536 1.1 rvb
537 1.14 perry coda_nc_remove(cncp, dcstat);
538 1.1 rvb }
539 1.1 rvb }
540 1.1 rvb }
541 1.1 rvb
542 1.1 rvb /*
543 1.1 rvb * Flush the entire name cache. In response to a flush of the Venus cache.
544 1.1 rvb */
545 1.1 rvb void
546 1.16 xtraeme coda_nc_flush(enum dc_status dcstat)
547 1.1 rvb {
548 1.1 rvb /* One option is to deallocate the current name cache and
549 1.1 rvb call init to start again. Or just deallocate, then rebuild.
550 1.14 perry Or again, we could just go through the array and zero the
551 1.14 perry appropriate fields.
552 1.1 rvb */
553 1.14 perry
554 1.14 perry /*
555 1.1 rvb * Go through the whole lru chain and kill everything as we go.
556 1.1 rvb * I don't use remove since that would rebuild the lru chain
557 1.1 rvb * as it went and that seemed unneccesary.
558 1.1 rvb */
559 1.3 rvb struct coda_cache *cncp;
560 1.1 rvb int i;
561 1.1 rvb
562 1.3 rvb if (coda_nc_use == 0) /* Cache is off */
563 1.1 rvb return;
564 1.1 rvb
565 1.3 rvb coda_nc_stat.Flushes++;
566 1.1 rvb
567 1.22 plunky TAILQ_FOREACH(cncp, &coda_nc_lru.head, lru) {
568 1.22 plunky if (CODA_NC_VALID(cncp)) { /* only zero valid nodes */
569 1.22 plunky LIST_REMOVE(cncp, hash);
570 1.22 plunky memset(&cncp->hash, 0, sizeof(cncp->hash));
571 1.1 rvb
572 1.14 perry if ((dcstat == IS_DOWNCALL)
573 1.1 rvb && (CTOV(cncp->dcp)->v_usecount == 1))
574 1.1 rvb {
575 1.1 rvb cncp->dcp->c_flags |= C_PURGING;
576 1.1 rvb }
577 1.14 perry vrele(CTOV(cncp->dcp));
578 1.1 rvb
579 1.21 ad if (CTOV(cncp->cp)->v_iflag & VI_TEXT) {
580 1.3 rvb if (coda_vmflush(cncp->cp))
581 1.14 perry CODADEBUG(CODA_FLUSH,
582 1.13 drochner myprintf(("coda_nc_flush: %s busy\n",
583 1.13 drochner coda_f2s(&cncp->cp->c_fid))); )
584 1.1 rvb }
585 1.1 rvb
586 1.14 perry if ((dcstat == IS_DOWNCALL)
587 1.1 rvb && (CTOV(cncp->cp)->v_usecount == 1))
588 1.1 rvb {
589 1.1 rvb cncp->cp->c_flags |= C_PURGING;
590 1.1 rvb }
591 1.14 perry vrele(CTOV(cncp->cp));
592 1.1 rvb
593 1.18 elad kauth_cred_free(cncp->cred);
594 1.10 thorpej memset(DATA_PART(cncp), 0, DATA_SIZE);
595 1.1 rvb }
596 1.1 rvb }
597 1.1 rvb
598 1.3 rvb for (i = 0; i < coda_nc_hashsize; i++)
599 1.3 rvb coda_nc_hash[i].length = 0;
600 1.1 rvb }
601 1.1 rvb
602 1.1 rvb /*
603 1.1 rvb * Debugging routines
604 1.1 rvb */
605 1.1 rvb
606 1.14 perry /*
607 1.1 rvb * This routine should print out all the hash chains to the console.
608 1.1 rvb */
609 1.1 rvb void
610 1.3 rvb print_coda_nc(void)
611 1.1 rvb {
612 1.1 rvb int hash;
613 1.3 rvb struct coda_cache *cncp;
614 1.1 rvb
615 1.3 rvb for (hash = 0; hash < coda_nc_hashsize; hash++) {
616 1.1 rvb myprintf(("\nhash %d\n",hash));
617 1.1 rvb
618 1.22 plunky LIST_FOREACH(cncp, &coda_nc_hash[hash].head, hash) {
619 1.1 rvb myprintf(("cp %p dcp %p cred %p name %s\n",
620 1.1 rvb cncp->cp, cncp->dcp,
621 1.1 rvb cncp->cred, cncp->name));
622 1.1 rvb }
623 1.1 rvb }
624 1.1 rvb }
625 1.1 rvb
626 1.1 rvb void
627 1.3 rvb coda_nc_gather_stats(void)
628 1.1 rvb {
629 1.15 christos int i, xmax = 0, sum = 0, temp, zeros = 0, ave, n;
630 1.1 rvb
631 1.3 rvb for (i = 0; i < coda_nc_hashsize; i++) {
632 1.3 rvb if (coda_nc_hash[i].length) {
633 1.3 rvb sum += coda_nc_hash[i].length;
634 1.1 rvb } else {
635 1.1 rvb zeros++;
636 1.1 rvb }
637 1.1 rvb
638 1.15 christos if (coda_nc_hash[i].length > xmax)
639 1.15 christos xmax = coda_nc_hash[i].length;
640 1.1 rvb }
641 1.1 rvb
642 1.1 rvb /*
643 1.14 perry * When computing the Arithmetic mean, only count slots which
644 1.1 rvb * are not empty in the distribution.
645 1.1 rvb */
646 1.3 rvb coda_nc_stat.Sum_bucket_len = sum;
647 1.3 rvb coda_nc_stat.Num_zero_len = zeros;
648 1.15 christos coda_nc_stat.Max_bucket_len = xmax;
649 1.1 rvb
650 1.14 perry if ((n = coda_nc_hashsize - zeros) > 0)
651 1.1 rvb ave = sum / n;
652 1.1 rvb else
653 1.1 rvb ave = 0;
654 1.1 rvb
655 1.1 rvb sum = 0;
656 1.3 rvb for (i = 0; i < coda_nc_hashsize; i++) {
657 1.3 rvb if (coda_nc_hash[i].length) {
658 1.3 rvb temp = coda_nc_hash[i].length - ave;
659 1.1 rvb sum += temp * temp;
660 1.1 rvb }
661 1.1 rvb }
662 1.3 rvb coda_nc_stat.Sum2_bucket_len = sum;
663 1.1 rvb }
664 1.1 rvb
665 1.1 rvb /*
666 1.1 rvb * The purpose of this routine is to allow the hash and cache sizes to be
667 1.1 rvb * changed dynamically. This should only be used in controlled environments,
668 1.1 rvb * it makes no effort to lock other users from accessing the cache while it
669 1.1 rvb * is in an improper state (except by turning the cache off).
670 1.1 rvb */
671 1.1 rvb int
672 1.16 xtraeme coda_nc_resize(int hashsize, int heapsize, enum dc_status dcstat)
673 1.1 rvb {
674 1.1 rvb if ((hashsize % 2) || (heapsize % 2)) { /* Illegal hash or cache sizes */
675 1.1 rvb return(EINVAL);
676 1.14 perry }
677 1.14 perry
678 1.3 rvb coda_nc_use = 0; /* Turn the cache off */
679 1.14 perry
680 1.3 rvb coda_nc_flush(dcstat); /* free any cnodes in the cache */
681 1.14 perry
682 1.1 rvb /* WARNING: free must happen *before* size is reset */
683 1.3 rvb CODA_FREE(coda_nc_heap,TOTAL_CACHE_SIZE);
684 1.3 rvb CODA_FREE(coda_nc_hash,TOTAL_HASH_SIZE);
685 1.14 perry
686 1.3 rvb coda_nc_hashsize = hashsize;
687 1.3 rvb coda_nc_size = heapsize;
688 1.14 perry
689 1.3 rvb coda_nc_init(); /* Set up a cache with the new size */
690 1.14 perry
691 1.3 rvb coda_nc_use = 1; /* Turn the cache back on */
692 1.1 rvb return(0);
693 1.1 rvb }
694 1.1 rvb
695 1.3 rvb char coda_nc_name_buf[CODA_MAXNAMLEN+1];
696 1.1 rvb
697 1.1 rvb void
698 1.3 rvb coda_nc_name(struct cnode *cp)
699 1.1 rvb {
700 1.22 plunky struct coda_cache *cncp;
701 1.1 rvb int i;
702 1.1 rvb
703 1.3 rvb if (coda_nc_use == 0) /* Cache is off */
704 1.1 rvb return;
705 1.1 rvb
706 1.3 rvb for (i = 0; i < coda_nc_hashsize; i++) {
707 1.22 plunky
708 1.22 plunky LIST_FOREACH(cncp, &coda_nc_hash[i].head, hash) {
709 1.1 rvb if (cncp->cp == cp) {
710 1.24 tsutsui memcpy(coda_nc_name_buf, cncp->name, cncp->namelen);
711 1.3 rvb coda_nc_name_buf[cncp->namelen] = 0;
712 1.1 rvb printf(" is %s (%p,%p)@%p",
713 1.3 rvb coda_nc_name_buf, cncp->cp, cncp->dcp, cncp);
714 1.1 rvb }
715 1.1 rvb
716 1.1 rvb }
717 1.1 rvb }
718 1.1 rvb }
719