usr/src/cmd/fs.d/cachefs/cfsd/cfsd_cache.c

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License, Version 1.0 only
   6  * (the "License").  You may not use this file except in compliance
   7  * with the License.
   8  *
   9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
  10  * or http://www.opensolaris.org/os/licensing.
  11  * See the License for the specific language governing permissions
  12  * and limitations under the License.
  13  *
  14  * When distributing Covered Code, include this CDDL HEADER in each
  15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  16  * If applicable, add the following below this CDDL HEADER, with the
  17  * fields enclosed by brackets "[]" replaced with your own identifying
  18  * information: Portions Copyright [yyyy] [name of copyright owner]
  19  *
  20  * CDDL HEADER END
  21  */
  22 /*
  23  * Copyright (c) 1994-2001 by Sun Microsystems, Inc.
  24  * All rights reserved.
  25  */
  26
  27 #pragma ident   "%Z%%M% %I%     %E% SMI"
  28
  29 /*
  30  * Methods of the cfsd_cache class.
  31  */
  32
  33 #include <stdio.h>
  34 #include <stdlib.h>
  35 #include <string.h>
  36 #include <thread.h>
  37 #include <synch.h>
  38 #include <locale.h>
  39 #include <sys/utsname.h>
  40 #include <sys/stat.h>
  41 #include <mdbug/mdbug.h>
  42 #include <sys/fs/cachefs_fs.h>
  43 #include <sys/fs/cachefs_dlog.h>
  44 #include <sys/fs/cachefs_ioctl.h>
  45 #include "cfsd.h"
  46 #include "cfsd_kmod.h"
  47 #include "cfsd_maptbl.h"
  48 #include "cfsd_logfile.h"
  49 #include "cfsd_fscache.h"
  50 #include "cfsd_cache.h"
  51
  52 /*
  53  * -----------------------------------------------------------------
  54  *                      cfsd_cache_create
  55  *
  56  * Description:
  57  * Arguments:
  58  * Returns:
  59  * Preconditions:
  60  */
  61
  62 cfsd_cache_object_t *
  63 cfsd_cache_create(void)
  64 {
  65         cfsd_cache_object_t *cache_object_p;
  66         int xx;
  67
  68         dbug_enter("cfsd_cache_create");
  69
  70         cache_object_p = cfsd_calloc(sizeof (cfsd_cache_object_t));
  71         strlcpy(cache_object_p->i_cachedir, gettext("unknown"),
  72             sizeof (cache_object_p->i_cachedir));
  73         cache_object_p->i_refcnt = 0;
  74         cache_object_p->i_nextfscacheid = 0;
  75         cache_object_p->i_cacheid = 0;
  76         cache_object_p->i_modify = 1;
  77         cache_object_p->i_fscachelist = NULL;
  78         cache_object_p->i_fscachecount = 0;
  79
  80         /* initialize the locking mutex */
  81         xx = mutex_init(&cache_object_p->i_lock, USYNC_THREAD, NULL);
  82
  83         dbug_assert(xx == 0);
  84         dbug_leave("cfsd_cache_create");
  85         return (cache_object_p);
  86 }
  87
  88 /*
  89  * -----------------------------------------------------------------
  90  *                      cfsd_cache_destroy
  91  *
  92  * Description:
  93  * Arguments:
  94  * Returns:
  95  * Preconditions:
  96  */
  97
  98
  99 void
 100 cfsd_cache_destroy(cfsd_cache_object_t *cache_object_p)
 101 {
 102
 103         cfsd_fscache_object_t *fscache_object_p;
 104         cfsd_fscache_object_t *tmp_fscache_object_p;
 105         int xx;
 106
 107         dbug_enter("cfsd_cache_destroy");
 108
 109         /* get rid of any fscache objects */
 110         fscache_object_p = cache_object_p->i_fscachelist;
 111
 112         while (fscache_object_p != NULL) {
 113                 tmp_fscache_object_p = fscache_object_p->i_next;
 114                 cfsd_fscache_destroy(fscache_object_p);
 115                 fscache_object_p = tmp_fscache_object_p;
 116         }
 117
 118         /* destroy the locking mutex */
 119         xx = mutex_destroy(&cache_object_p->i_lock);
 120         dbug_assert(xx == 0);
 121         cfsd_free(cache_object_p);
 122         dbug_leave("cfsd_cache_destroy");
 123 }
 124
 125 /*
 126  * -----------------------------------------------------------------
 127  *                      cache_setup
 128  *
 129  * Description:
 130  *      Performs setup for the cache.
 131  * Arguments:
 132  *      cachedirp
 133  *      cacheid
 134  * Returns:
 135  * Preconditions:
 136  *      precond(cachedirp)
 137  */
 138
 139 int
 140 cache_setup(cfsd_cache_object_t *cache_object_p, const char *cachedirp,
 141         int cacheid)
 142 {
 143
 144         /* XXX either need to prevent multiple calls to this or */
 145         /*  clean up here. */
 146
 147         int ret;
 148         struct stat64 sinfo;
 149         dbug_enter("cache_setup");
 150
 151         if ((stat64(cachedirp, &sinfo) == -1) ||
 152             (!S_ISDIR(sinfo.st_mode)) ||
 153             (*cachedirp != '/')) {
 154                 dbug_print(("info", "%s is not a cache directory", cachedirp));
 155                 ret = 0;
 156         } else {
 157                 strlcpy(cache_object_p->i_cachedir, cachedirp,
 158                     sizeof (cache_object_p->i_cachedir));
 159                 ret = 1;
 160         }
 161
 162         cache_object_p->i_cacheid = cacheid;
 163         cache_object_p->i_modify++;
 164
 165         dbug_leave("cache_setup");
 166         /* return result */
 167         return (ret);
 168 }
 169 /*
 170  * -----------------------------------------------------------------
 171  *                      cache_lock
 172  *
 173  * Description:
 174  * Arguments:
 175  * Returns:
 176  * Preconditions:
 177  */
 178
 179 void
 180 cache_lock(cfsd_cache_object_t *cache_object_p)
 181 {
 182         dbug_enter("cache_lock");
 183
 184         mutex_lock(&cache_object_p->i_lock);
 185         dbug_leave("cache_lock");
 186 }
 187
 188 /*
 189  * -----------------------------------------------------------------
 190  *                      cache_unlock
 191  *
 192  * Description:
 193  * Arguments:
 194  * Returns:
 195  * Preconditions:
 196  */
 197
 198 void
 199 cache_unlock(cfsd_cache_object_t *cache_object_p)
 200 {
 201         dbug_enter("cache_unlock");
 202
 203         mutex_unlock(&cache_object_p->i_lock);
 204         dbug_leave("cache_unlock");
 205 }
 206 /*
 207  * -----------------------------------------------------------------
 208  *                      cache_fscachelist_at
 209  *
 210  * Description:
 211  * Arguments:
 212  *      index
 213  * Returns:
 214  *      Returns ...
 215  * Preconditions:
 216  */
 217
 218 cfsd_fscache_object_t *
 219 cache_fscachelist_at(cfsd_cache_object_t *cache_object_p, size_t index)
 220 {
 221         cfsd_fscache_object_t *fscache_object_p;
 222         int i = 0;
 223
 224         dbug_enter("cache_fscachelist_at");
 225
 226         /* find the correct cache object */
 227         fscache_object_p = cache_object_p->i_fscachelist;
 228
 229         while ((fscache_object_p != NULL) && (i++ < index)) {
 230                 fscache_object_p = fscache_object_p->i_next;
 231         }
 232
 233         dbug_leave("cache_fscachelist_at");
 234         return (fscache_object_p);
 235 }
 236
 237 /*
 238  * -----------------------------------------------------------------
 239  *                      cache_fscachelist_add
 240  *
 241  * Description:
 242  * Arguments:
 243  *      cachep
 244  * Returns:
 245  * Preconditions:
 246  *      precond(fscachep)
 247  */
 248
 249 void
 250 cache_fscachelist_add(cfsd_cache_object_t *cache_object_p,
 251         cfsd_fscache_object_t *fscache_object_p)
 252 {
 253         dbug_enter("cache_fscachelist_add");
 254
 255         dbug_precond(fscache_object_p);
 256
 257         fscache_object_p->i_next = cache_object_p->i_fscachelist;
 258         cache_object_p->i_fscachelist = fscache_object_p;
 259         cache_object_p->i_modify++;
 260         cache_object_p->i_fscachecount++;
 261         dbug_leave("cache_fscachelist_add");
 262 }
 263
 264 /*
 265  * -----------------------------------------------------------------
 266  *                      cache_fscachelist_find
 267  *
 268  * Description:
 269  * Arguments:
 270  *      namep
 271  * Returns:
 272  *      Returns ...
 273  * Preconditions:
 274  *      precond(namep)
 275  */
 276
 277 cfsd_fscache_object_t *
 278 cache_fscachelist_find(cfsd_cache_object_t *cache_object_p,
 279         const char *namep)
 280 {
 281         cfsd_fscache_object_t *fscache_object_p;
 282
 283         dbug_enter("cache_fscachelist_find");
 284
 285         dbug_precond(namep);
 286
 287         /* see if the fscache exists */
 288         fscache_object_p = cache_object_p->i_fscachelist;
 289
 290         while ((fscache_object_p != NULL) &&
 291                 strcmp(namep, fscache_object_p->i_name)) {
 292                 fscache_object_p = fscache_object_p->i_next;
 293         }
 294
 295         dbug_leave("cache_fscachelist_find");
 296         return (fscache_object_p);
 297 }