3 * Coda: an Experimental Distributed File System
6 * Copyright (c) 1987-1998 Carnegie Mellon University
9 * Permission to use, copy, modify and distribute this software and its
10 * documentation is hereby granted, provided that both the copyright
11 * notice and this permission notice appear in all copies of the
12 * software, derivative works or modified versions, and any portions
13 * thereof, and that both notices appear in supporting documentation, and
14 * that credit is given to Carnegie Mellon University in all documents
15 * and publicity pertaining to direct or indirect use of this code or its
18 * CODA IS AN EXPERIMENTAL SOFTWARE SYSTEM AND IS KNOWN TO HAVE BUGS,
19 * SOME OF WHICH MAY HAVE SERIOUS CONSEQUENCES. CARNEGIE MELLON ALLOWS
20 * FREE USE OF THIS SOFTWARE IN ITS "AS IS" CONDITION. CARNEGIE MELLON
21 * DISCLAIMS ANY LIABILITY OF ANY KIND FOR ANY DAMAGES WHATSOEVER
22 * RESULTING DIRECTLY OR INDIRECTLY FROM THE USE OF THIS SOFTWARE OR OF
23 * ANY DERIVATIVE WORK.
25 * Carnegie Mellon encourages users of this software to return any
26 * improvements or extensions that they make, and to grant Carnegie
27 * Mellon the rights to redistribute these changes without encumbrance.
29 * @(#) src/sys/coda/coda_namecache.h,v 1.1.1.1 1998/08/29 21:14:52 rvb Exp $
30 * $Id: coda_namecache.h,v 1.3 1998/09/11 18:50:17 rvb Exp $
35 * Mach Operating System
36 * Copyright (c) 1990 Carnegie-Mellon University
37 * Copyright (c) 1989 Carnegie-Mellon University
38 * All rights reserved. The CMU software License Agreement specifies
39 * the terms and conditions for use and redistribution.
43 * This code was written for the Coda file system at Carnegie Mellon University.
44 * Contributers include David Steere, James Kistler, and M. Satyanarayanan.
49 * $Log: coda_namecache.h,v $
50 * Revision 1.3 1998/09/11 18:50:17 rvb
51 * All the references to cfs, in symbols, structs, and strings
52 * have been changed to coda. (Same for CFS.)
54 * Revision 1.2 1998/09/02 19:09:53 rvb
57 * Revision 1.1.1.1 1998/08/29 21:14:52 rvb
58 * Very Preliminary Coda
60 * Revision 1.8 1998/08/28 18:12:25 rvb
61 * Now it also works on FreeBSD -current. This code will be
62 * committed to the FreeBSD -current and NetBSD -current
63 * trees. It will then be tailored to the particular platform
64 * by flushing conditional code.
66 * Revision 1.7 1998/08/18 17:05:24 rvb
67 * Don't use __RCSID now
69 * Revision 1.6 1998/08/18 16:31:49 rvb
70 * Sync the code for NetBSD -current; test on 1.3 later
72 * Revision 1.5 98/01/23 11:53:51 rvb
73 * Bring RVB_CODA1_1 to HEAD
75 * Revision 1.4.2.1 97/12/16 12:40:23 rvb
78 * Revision 1.4 97/12/05 10:39:29 rvb
81 * Revision 1.3.4.3 97/11/24 15:44:51 rvb
82 * Final cfs_venus.c w/o macros, but one locking bug
84 * Revision 1.3.4.2 97/11/12 12:09:44 rvb
87 * Revision 1.3.4.1 97/11/06 21:06:05 rvb
88 * don't include headers in headers
90 * Revision 1.3 97/08/05 11:08:19 lily
91 * Removed cfsnc_replace, replaced it with a coda_find, unhash, and
92 * rehash. This fixes a cnode leak and a bug in which the fid is
93 * not actually replaced. (cfs_namecache.c, cfsnc.h, cfs_subr.c)
95 * Revision 1.2 96/01/02 16:57:19 bnoble
96 * Added support for Coda MiniCache and raw inode calls (final commit)
98 * Revision 1.1.2.1 1995/12/20 01:57:45 bnoble
99 * Added CODA-specific files
101 * Revision 3.1.1.1 1995/03/04 19:08:22 bnoble
102 * Branch for NetBSD port revisions
104 * Revision 3.1 1995/03/04 19:08:21 bnoble
105 * Bump to major revision 3 to prepare for NetBSD port
107 * Revision 2.2 1994/08/28 19:37:39 luqi
108 * Add a new CODA_REPLACE call to allow venus to replace a ViceFid in the
112 * Add CODA_REPLACE decl.
114 * In "cfs_namecache.c":
115 * Add routine cfsnc_replace.
118 * Add case-statement to process CODA_REPLACE.
121 * Add decl for CODA_NC_REPLACE.
123 * Revision 2.1 94/07/21 16:25:27 satya
124 * Conversion to C++ 3.0; start of Coda Release 2.0
126 * Revision 1.2 92/10/27 17:58:34 lily
127 * merge kernel/latest and alpha/src/cfs
129 * Revision 2.2 90/07/05 11:27:04 mrt
130 * Created for the Coda File System.
133 * Revision 1.4 90/05/31 17:02:12 dcs
134 * Prepare for merge with facilities kernel.
138 #ifndef _CODA_NC_HEADER_
139 #define _CODA_NC_HEADER_
144 #define CODA_NC_NAMELEN 15 /* longest name stored in cache */
145 #define CODA_NC_CACHESIZE 256 /* Default cache size */
146 #define CODA_NC_HASHSIZE 64 /* Must be multiple of 2 */
149 * Hash function for the primary hash.
153 * First try -- (first + last letters + length + (int)cp) mod size
154 * 2nd try -- same, except dir fid.vnode instead of cp
158 #define CODA_NC_HASH(name, namelen, cp) \
159 ((name[0] + name[namelen-1] + namelen + (int)(cp)) & (coda_nc_hashsize-1))
161 #define CODA_NC_HASH(name, namelen, cp) \
162 ((name[0] + (name[namelen-1]<<4) + namelen + (((int)cp)>>8)) & (coda_nc_hashsize-1))
165 #define CODA_NAMEMATCH(cp, name, namelen, dcp) \
166 ((namelen == cp->namelen) && (dcp == cp->dcp) && \
167 (bcmp(cp->name,name,namelen) == 0))
170 * Functions to modify the hash and lru chains.
171 * insque and remque assume that the pointers are the first thing
172 * in the list node, thus the trickery for lru.
175 #define CODA_NC_HSHINS(elem, pred) insque(elem,pred)
176 #define CODA_NC_HSHREM(elem) remque(elem)
177 #define CODA_NC_HSHNUL(elem) (elem)->hash_next = \
178 (elem)->hash_prev = (elem)
180 #define CODA_NC_LRUINS(elem, pred) insque(LRU_PART(elem), LRU_PART(pred))
181 #define CODA_NC_LRUREM(elem) remque(LRU_PART(elem));
182 #define CODA_NC_LRUGET(lruhead) LRU_TOP((lruhead).lru_prev)
184 #define CODA_NC_VALID(cncp) (cncp->dcp != (struct cnode *)0)
186 #define LRU_PART(cncp) (struct coda_cache *) \
187 ((char *)cncp + (2*sizeof(struct coda_cache *)))
188 #define LRU_TOP(cncp) (struct coda_cache *) \
189 ((char *)cncp - (2*sizeof(struct coda_cache *)))
190 #define DATA_PART(cncp) (struct coda_cache *) \
191 ((char *)cncp + (4*sizeof(struct coda_cache *)))
192 #define DATA_SIZE (sizeof(struct coda_cache)-(4*sizeof(struct coda_cache *)))
195 * Structure for an element in the CODA Name Cache.
196 * NOTE: I use the position of arguments and their size in the
197 * implementation of the functions CODA_NC_LRUINS, CODA_NC_LRUREM, and
202 struct coda_cache *hash_next,*hash_prev; /* Hash list */
203 struct coda_cache *lru_next, *lru_prev; /* LRU list */
204 struct cnode *cp; /* vnode of the file */
205 struct cnode *dcp; /* parent's cnode */
206 struct ucred *cred; /* user credentials */
207 char name[CODA_NC_NAMELEN]; /* segment name */
208 int namelen; /* length of name */
211 struct coda_lru { /* Start of LRU chain */
212 char *dummy1, *dummy2; /* place holders */
213 struct coda_cache *lru_next, *lru_prev; /* position of pointers is important */
217 struct coda_hash { /* Start of Hash chain */
218 struct coda_cache *hash_next, *hash_prev; /* NOTE: chain pointers must be first */
219 int length; /* used for tuning purposes */
224 * Symbols to aid in debugging the namecache code. Assumes the existence
225 * of the variable coda_nc_debug, which is defined in cfs_namecache.c
227 #define CODA_NC_DEBUG(N, STMT) { if (coda_nc_debug & (1 <<N)) { STMT } }
229 /* Prototypes of functions exported within cfs */
230 extern void coda_nc_init(void);
231 extern void coda_nc_enter(struct cnode *, const char *, int, struct ucred *, struct cnode *);
232 extern struct cnode *coda_nc_lookup(struct cnode *, const char *, int, struct ucred *);
234 extern void coda_nc_zapParentfid(ViceFid *, enum dc_status);
235 extern void coda_nc_zapfid(ViceFid *, enum dc_status);
236 extern void coda_nc_zapvnode(ViceFid *, struct ucred *, enum dc_status);
237 extern void coda_nc_zapfile(struct cnode *, const char *, int);
238 extern void coda_nc_purge_user(vuid_t, enum dc_status);
239 extern void coda_nc_flush(enum dc_status);
241 extern void print_coda_nc(void);
242 extern void coda_nc_gather_stats(void);
243 extern int coda_nc_resize(int, int, enum dc_status);
244 extern void coda_nc_name(struct cnode *cp);
247 * Structure to contain statistics on the cache usage
250 struct coda_nc_statistics {
255 unsigned long_name_enters;
256 unsigned long_name_lookups;
257 unsigned long_remove;
264 unsigned Sum_bucket_len;
265 unsigned Sum2_bucket_len;
266 unsigned Max_bucket_len;
267 unsigned Num_zero_len;
271 #define CODA_NC_FIND ((u_long) 1)
272 #define CODA_NC_REMOVE ((u_long) 2)
273 #define CODA_NC_INIT ((u_long) 3)
274 #define CODA_NC_ENTER ((u_long) 4)
275 #define CODA_NC_LOOKUP ((u_long) 5)
276 #define CODA_NC_ZAPPFID ((u_long) 6)
277 #define CODA_NC_ZAPFID ((u_long) 7)
278 #define CODA_NC_ZAPVNODE ((u_long) 8)
279 #define CODA_NC_ZAPFILE ((u_long) 9)
280 #define CODA_NC_PURGEUSER ((u_long) 10)
281 #define CODA_NC_FLUSH ((u_long) 11)
282 #define CODA_NC_PRINTCODA_NC ((u_long) 12)
283 #define CODA_NC_PRINTSTATS ((u_long) 13)