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 2004 Sun Microsystems, Inc. All rights reserved.
24 * Use is subject to license terms.
25 * Copyright (c) 2011 Bayard G. Bell. All rights reserved.
26 */
27
28 #include <sys/errno.h>
29 #include <sys/param.h>
30 #include <sys/types.h>
31 #include <sys/user.h>
32 #include <sys/stat.h>
33 #include <sys/time.h>
34 #include <sys/vfs.h>
35 #include <sys/vnode.h>
36 #include <rpc/types.h>
37 #include <sys/mode.h>
38 #include <sys/cmn_err.h>
39 #include <sys/debug.h>
40 #include <sys/fs/cachefs_fs.h>
41
42 /*
43 * This is the loadable module wrapper.
44 */
45 #include <sys/systm.h>
46 #include <sys/modctl.h>
47 #include <sys/syscall.h>
48
49 extern time_t time;
50
51 static int cachefs_init(int, char *);
52 static void cachefs_fini();
53
54 static int cachefs_unloadable = 0; /* tunable */
55 static boolean_t cachefs_up = B_FALSE;
56
57 uint_t cachefs_max_apop_inqueue = CACHEFS_MAX_APOP_INQUEUE;
58
59 /*
60 * this is a list of possible hash table sizes, for the `double
61 * hashing' algorithm described in rosen's `elementary number theory
62 * and its applications'. minimally, this needs to be a list of
63 * increasing prime integers, terminated by a 0. ideally, they should
64 * be the larger of twin primes; i.e. P and P-2 are both prime.
65 */
66
67 int cachefs_hash_sizes[] = {5, 2029, 4093, 8089, 16363, 32719, 0};
68
69 /*
70 * Module linkage information for the kernel.
71 */
72
73 static vfsdef_t vfs_z = {
74 VFSDEF_VERSION,
75 CACHEFS_BASETYPE,
76 cachefs_init,
77 VSW_CANREMOUNT,
78 NULL
79 };
80
81 static struct modlfs modlfs = {
82 &mod_fsops,
83 "cache filesystem",
84 &vfs_z
85 };
86
87 static struct modlinkage modlinkage = {
88 MODREV_1, (void *)&modlfs, NULL
89 };
90
91 int
92 _init(void)
93 {
94 int status;
95
96 status = mod_install(&modlinkage);
97 if (status != 0) {
98 /*
99 * Could not load module, clean up the work performed
100 * by cachefs_init() which was indirectly called by
101 * mod_installfs() which in turn was called by mod_install().
102 */
103 cachefs_fini();
104 }
105
106 return (status);
107 }
108
109 int
110 _info(struct modinfo *modinfop)
111 {
112 return (mod_info(&modlinkage, modinfop));
113 }
114
115 int
116 _fini(void)
117 {
118 int status;
119
120 if (!cachefs_unloadable)
121 return (EBUSY);
122
123 if ((status = mod_remove(&modlinkage)) == 0) {
124 /*
125 * Module has been unloaded, now clean up
126 */
127 cachefs_fini();
128 }
129
130 return (status);
131 }
132
133 extern kmutex_t cachefs_cachelock; /* Cache list mutex */
134 extern kmutex_t cachefs_newnum_lock;
135 extern kmutex_t cachefs_kstat_key_lock;
136 extern kmutex_t cachefs_rename_lock;
137 extern kmutex_t cachefs_minor_lock; /* Lock for minor device map */
138 extern kmutex_t cachefs_kmem_lock;
139 extern kmutex_t cachefs_async_lock; /* global async work count */
140 extern major_t cachefs_major;
141
142 /*
143 * Cache initialization routine. This routine should only be called
144 * once. It performs the following tasks:
145 * - Initalize all global locks
146 * - Call sub-initialization routines (localize access to variables)
147 */
148 static int
149 cachefs_init(int fstyp, char *name)
150 {
151 kstat_t *ksp;
152 int error;
153
154 ASSERT(cachefs_up == B_FALSE);
155
156 error = cachefs_init_vfsops(fstyp);
157 if (error != 0)
158 return (error);
159
160 error = cachefs_init_vnops(name);
161 if (error != 0)
162 return (error);
163
164 mutex_init(&cachefs_cachelock, NULL, MUTEX_DEFAULT, NULL);
165 mutex_init(&cachefs_newnum_lock, NULL, MUTEX_DEFAULT, NULL);
166 mutex_init(&cachefs_kstat_key_lock, NULL, MUTEX_DEFAULT, NULL);
167 mutex_init(&cachefs_kmem_lock, NULL, MUTEX_DEFAULT, NULL);
168 mutex_init(&cachefs_rename_lock, NULL, MUTEX_DEFAULT, NULL);
169 mutex_init(&cachefs_minor_lock, NULL, MUTEX_DEFAULT, NULL);
170 mutex_init(&cachefs_async_lock, NULL, MUTEX_DEFAULT, NULL);
171 #ifdef CFSRLDEBUG
172 mutex_init(&cachefs_rl_debug_mutex, NULL, MUTEX_DEFAULT, NULL);
173 #endif /* CFSRLDEBUG */
174
175 /*
176 * set up kmem_cache entities
177 */
178
179 cachefs_cnode_cache = kmem_cache_create("cachefs_cnode_cache",
180 sizeof (struct cnode), 0, NULL, NULL, NULL, NULL, NULL, 0);
181 cachefs_req_cache = kmem_cache_create("cachefs_async_request",
182 sizeof (struct cachefs_req), 0,
183 cachefs_req_create, cachefs_req_destroy, NULL, NULL, NULL, 0);
184 cachefs_fscache_cache = kmem_cache_create("cachefs_fscache",
185 sizeof (fscache_t), 0, NULL, NULL, NULL, NULL, NULL, 0);
186 cachefs_filegrp_cache = kmem_cache_create("cachefs_filegrp",
187 sizeof (filegrp_t), 0,
188 filegrp_cache_create, filegrp_cache_destroy, NULL, NULL, NULL, 0);
189 cachefs_cache_kmcache = kmem_cache_create("cachefs_cache_t",
190 sizeof (cachefscache_t), 0, NULL, NULL, NULL, NULL, NULL, 0);
191
192 /*
193 * set up the cachefs.0.key kstat
194 */
195
196 cachefs_kstat_key = NULL;
197 cachefs_kstat_key_n = 0;
198 ksp = kstat_create("cachefs", 0, "key", "misc", KSTAT_TYPE_RAW, 1,
199 KSTAT_FLAG_VIRTUAL | KSTAT_FLAG_VAR_SIZE);
200 if (ksp != NULL) {
201 ksp->ks_data = &cachefs_kstat_key;
202 ksp->ks_update = cachefs_kstat_key_update;
203 ksp->ks_snapshot = cachefs_kstat_key_snapshot;
204 ksp->ks_lock = &cachefs_kstat_key_lock;
205 kstat_install(ksp);
206 }
207
208 /*
209 * Assign unique major number for all nfs mounts
210 */
211
212 if ((cachefs_major = getudev()) == -1) {
213 cmn_err(CE_WARN,
214 "cachefs: init: can't get unique device number");
215 cachefs_major = 0;
216 }
217 cachefs_up = B_TRUE;
218 #ifdef CFSRLDEBUG
219 cachefs_dbvalid = time;
220 #endif /* CFSRLDEBUG */
221
222 return (0);
223 }
224
225 /*
226 * Cache clean up routine. This routine is called if mod_install() failed
227 * and we have to clean up because the module could not be installed,
228 * or by _fini() when we're unloading the module.
229 */
230 static void
231 cachefs_fini()
232 {
233 extern int cachefsfstyp;
234 extern struct vnodeops *cachefs_vnodeops;
235
236 if (cachefs_up == B_FALSE) {
237 /*
238 * cachefs_init() was not called on _init(),
239 * nothing to deallocate.
240 */
241 return;
242 }
243
244 /*
245 * Clean up cachefs.0.key kstat.
246 * Currently, you can only do a
247 * modunload if cachefs_unloadable is nonzero, and that's
248 * pretty much just for debugging. however, if there ever
249 * comes a day when cachefs is more freely unloadable
250 * (e.g. the modunload daemon can do it normally), then we'll
251 * have to make changes in the stats_ API. this is because a
252 * stats_cookie_t holds the id # derived from here, and it
253 * will all go away at modunload time. thus, the API will
254 * need to somehow be more robust than is currently necessary.
255 */
256 kstat_delete_byname("cachefs", 0, "key");
257
258 if (cachefs_kstat_key != NULL) {
259 cachefs_kstat_key_t *key;
260 int i;
261
262 for (i = 0; i < cachefs_kstat_key_n; i++) {
263 key = cachefs_kstat_key + i;
264
265 cachefs_kmem_free((void *)(uintptr_t)key->ks_mountpoint,
266 strlen((char *)(uintptr_t)key->ks_mountpoint) + 1);
267 cachefs_kmem_free((void *)(uintptr_t)key->ks_backfs,
268 strlen((char *)(uintptr_t)key->ks_backfs) + 1);
269 cachefs_kmem_free((void *)(uintptr_t)key->ks_cachedir,
270 strlen((char *)(uintptr_t)key->ks_cachedir) + 1);
271 cachefs_kmem_free((void *)(uintptr_t)key->ks_cacheid,
272 strlen((char *)(uintptr_t)key->ks_cacheid) + 1);
273 }
274
275 cachefs_kmem_free(cachefs_kstat_key,
276 cachefs_kstat_key_n * sizeof (*cachefs_kstat_key));
277 }
278
279 /*
280 * Clean up kmem_cache entities
281 */
282 kmem_cache_destroy(cachefs_cache_kmcache);
283 kmem_cache_destroy(cachefs_filegrp_cache);
284 kmem_cache_destroy(cachefs_fscache_cache);
285 kmem_cache_destroy(cachefs_req_cache);
286 kmem_cache_destroy(cachefs_cnode_cache);
287 #ifdef CFSRLDEBUG
288 if (cachefs_rl_debug_cache != NULL)
289 kmem_cache_destroy(cachefs_rl_debug_cache);
290 #endif /* CFSRLDEBUG */
291
292 /*
293 * Clean up the operations structures
294 */
295 (void) vfs_freevfsops_by_type(cachefsfstyp);
296 vn_freevnodeops(cachefs_vnodeops);
297
298 /*
299 * Destroy mutexes
300 */
301 #ifdef CFSRLDEBUG
302 mutex_destroy(&cachefs_rl_debug_mutex);
303 #endif /* CFSRLDEBUG */
304 mutex_destroy(&cachefs_async_lock);
305 mutex_destroy(&cachefs_minor_lock);
306 mutex_destroy(&cachefs_rename_lock);
307 mutex_destroy(&cachefs_kmem_lock);
308 mutex_destroy(&cachefs_kstat_key_lock);
309 mutex_destroy(&cachefs_newnum_lock);
310 mutex_destroy(&cachefs_cachelock);
311 }