blob: 584bb0f9c36a35cdd5ed4234a83ba927e0d04e5e [file] [log] [blame]
David Howellsec268152007-04-26 15:49:28 -07001/* AFS cell and server record management
Linus Torvalds1da177e2005-04-16 15:20:36 -07002 *
3 * Copyright (C) 2002 Red Hat, Inc. All Rights Reserved.
4 * Written by David Howells (dhowells@redhat.com)
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; either version
9 * 2 of the License, or (at your option) any later version.
10 */
11
12#include <linux/module.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070013#include <linux/slab.h>
David Howells00d3b7a2007-04-26 15:57:07 -070014#include <linux/key.h>
15#include <linux/ctype.h>
Alexey Dobriyane8edc6e2007-05-21 01:22:52 +040016#include <linux/sched.h>
David Howells00d3b7a2007-04-26 15:57:07 -070017#include <keys/rxrpc-type.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070018#include "internal.h"
19
20DECLARE_RWSEM(afs_proc_cells_sem);
21LIST_HEAD(afs_proc_cells);
22
23static struct list_head afs_cells = LIST_HEAD_INIT(afs_cells);
24static DEFINE_RWLOCK(afs_cells_lock);
25static DECLARE_RWSEM(afs_cells_sem); /* add/remove serialisation */
David Howells08e0e7c2007-04-26 15:55:03 -070026static DECLARE_WAIT_QUEUE_HEAD(afs_cells_freeable_wq);
Linus Torvalds1da177e2005-04-16 15:20:36 -070027static struct afs_cell *afs_cell_root;
28
Linus Torvalds1da177e2005-04-16 15:20:36 -070029/*
David Howells00d3b7a2007-04-26 15:57:07 -070030 * allocate a cell record and fill in its name, VL server address list and
31 * allocate an anonymous key
Linus Torvalds1da177e2005-04-16 15:20:36 -070032 */
David Howells00d3b7a2007-04-26 15:57:07 -070033static struct afs_cell *afs_cell_alloc(const char *name, char *vllist)
Linus Torvalds1da177e2005-04-16 15:20:36 -070034{
35 struct afs_cell *cell;
David Howells76181c12007-10-16 23:29:46 -070036 struct key *key;
David Howells00d3b7a2007-04-26 15:57:07 -070037 size_t namelen;
38 char keyname[4 + AFS_MAXCELLNAME + 1], *cp, *dp, *next;
Linus Torvalds1da177e2005-04-16 15:20:36 -070039 int ret;
40
David Howells08e0e7c2007-04-26 15:55:03 -070041 _enter("%s,%s", name, vllist);
Linus Torvalds1da177e2005-04-16 15:20:36 -070042
43 BUG_ON(!name); /* TODO: want to look up "this cell" in the cache */
44
David Howells00d3b7a2007-04-26 15:57:07 -070045 namelen = strlen(name);
46 if (namelen > AFS_MAXCELLNAME)
47 return ERR_PTR(-ENAMETOOLONG);
48
Linus Torvalds1da177e2005-04-16 15:20:36 -070049 /* allocate and initialise a cell record */
David Howells00d3b7a2007-04-26 15:57:07 -070050 cell = kzalloc(sizeof(struct afs_cell) + namelen + 1, GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -070051 if (!cell) {
52 _leave(" = -ENOMEM");
David Howells08e0e7c2007-04-26 15:55:03 -070053 return ERR_PTR(-ENOMEM);
Linus Torvalds1da177e2005-04-16 15:20:36 -070054 }
55
David Howells00d3b7a2007-04-26 15:57:07 -070056 memcpy(cell->name, name, namelen);
57 cell->name[namelen] = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -070058
David Howells08e0e7c2007-04-26 15:55:03 -070059 atomic_set(&cell->usage, 1);
Linus Torvalds1da177e2005-04-16 15:20:36 -070060 INIT_LIST_HEAD(&cell->link);
David Howells08e0e7c2007-04-26 15:55:03 -070061 rwlock_init(&cell->servers_lock);
62 INIT_LIST_HEAD(&cell->servers);
Linus Torvalds1da177e2005-04-16 15:20:36 -070063 init_rwsem(&cell->vl_sem);
64 INIT_LIST_HEAD(&cell->vl_list);
David Howells08e0e7c2007-04-26 15:55:03 -070065 spin_lock_init(&cell->vl_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -070066
Linus Torvalds1da177e2005-04-16 15:20:36 -070067 /* fill in the VL server list from the rest of the string */
Linus Torvalds1da177e2005-04-16 15:20:36 -070068 do {
69 unsigned a, b, c, d;
70
71 next = strchr(vllist, ':');
72 if (next)
73 *next++ = 0;
74
75 if (sscanf(vllist, "%u.%u.%u.%u", &a, &b, &c, &d) != 4)
David Howells00d3b7a2007-04-26 15:57:07 -070076 goto bad_address;
Linus Torvalds1da177e2005-04-16 15:20:36 -070077
78 if (a > 255 || b > 255 || c > 255 || d > 255)
David Howells00d3b7a2007-04-26 15:57:07 -070079 goto bad_address;
Linus Torvalds1da177e2005-04-16 15:20:36 -070080
81 cell->vl_addrs[cell->vl_naddrs++].s_addr =
82 htonl((a << 24) | (b << 16) | (c << 8) | d);
83
David Howells00d3b7a2007-04-26 15:57:07 -070084 } while (cell->vl_naddrs < AFS_CELL_MAX_ADDRS && (vllist = next));
Linus Torvalds1da177e2005-04-16 15:20:36 -070085
David Howells00d3b7a2007-04-26 15:57:07 -070086 /* create a key to represent an anonymous user */
87 memcpy(keyname, "afs@", 4);
88 dp = keyname + 4;
89 cp = cell->name;
90 do {
91 *dp++ = toupper(*cp);
92 } while (*cp++);
David Howells00d3b7a2007-04-26 15:57:07 -070093
David Howells76181c12007-10-16 23:29:46 -070094 key = rxrpc_get_null_key(keyname);
95 if (IS_ERR(key)) {
96 _debug("no key");
97 ret = PTR_ERR(key);
David Howells00d3b7a2007-04-26 15:57:07 -070098 goto error;
99 }
David Howells76181c12007-10-16 23:29:46 -0700100 cell->anonymous_key = key;
David Howells00d3b7a2007-04-26 15:57:07 -0700101
102 _debug("anon key %p{%x}",
103 cell->anonymous_key, key_serial(cell->anonymous_key));
104
105 _leave(" = %p", cell);
106 return cell;
107
108bad_address:
109 printk(KERN_ERR "kAFS: bad VL server IP address\n");
110 ret = -EINVAL;
111error:
112 key_put(cell->anonymous_key);
113 kfree(cell);
114 _leave(" = %d", ret);
115 return ERR_PTR(ret);
116}
117
118/*
119 * create a cell record
120 * - "name" is the name of the cell
121 * - "vllist" is a colon separated list of IP addresses in "a.b.c.d" format
122 */
123struct afs_cell *afs_cell_create(const char *name, char *vllist)
124{
125 struct afs_cell *cell;
126 int ret;
127
128 _enter("%s,%s", name, vllist);
129
Sven Schnelle5214b722008-03-28 14:15:55 -0700130 down_write(&afs_cells_sem);
131 read_lock(&afs_cells_lock);
132 list_for_each_entry(cell, &afs_cells, link) {
133 if (strcasecmp(cell->name, name) == 0)
134 goto duplicate_name;
135 }
136 read_unlock(&afs_cells_lock);
137
David Howells00d3b7a2007-04-26 15:57:07 -0700138 cell = afs_cell_alloc(name, vllist);
139 if (IS_ERR(cell)) {
140 _leave(" = %ld", PTR_ERR(cell));
Sven Schnellea5f37c32008-04-02 13:17:18 +0100141 up_write(&afs_cells_sem);
David Howells00d3b7a2007-04-26 15:57:07 -0700142 return cell;
143 }
144
David Howells08e0e7c2007-04-26 15:55:03 -0700145 /* add a proc directory for this cell */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700146 ret = afs_proc_cell_setup(cell);
147 if (ret < 0)
148 goto error;
149
150#ifdef AFS_CACHING_SUPPORT
151 /* put it up for caching */
152 cachefs_acquire_cookie(afs_cache_netfs.primary_index,
153 &afs_vlocation_cache_index_def,
154 cell,
155 &cell->cache);
156#endif
157
158 /* add to the cell lists */
159 write_lock(&afs_cells_lock);
160 list_add_tail(&cell->link, &afs_cells);
161 write_unlock(&afs_cells_lock);
162
163 down_write(&afs_proc_cells_sem);
164 list_add_tail(&cell->proc_link, &afs_proc_cells);
165 up_write(&afs_proc_cells_sem);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700166 up_write(&afs_cells_sem);
167
David Howells08e0e7c2007-04-26 15:55:03 -0700168 _leave(" = %p", cell);
169 return cell;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700170
David Howellsec268152007-04-26 15:49:28 -0700171error:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700172 up_write(&afs_cells_sem);
David Howells00d3b7a2007-04-26 15:57:07 -0700173 key_put(cell->anonymous_key);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700174 kfree(cell);
175 _leave(" = %d", ret);
David Howells08e0e7c2007-04-26 15:55:03 -0700176 return ERR_PTR(ret);
Sven Schnelle5214b722008-03-28 14:15:55 -0700177
178duplicate_name:
179 read_unlock(&afs_cells_lock);
180 up_write(&afs_cells_sem);
181 return ERR_PTR(-EEXIST);
David Howellsec268152007-04-26 15:49:28 -0700182}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700183
Linus Torvalds1da177e2005-04-16 15:20:36 -0700184/*
David Howells08e0e7c2007-04-26 15:55:03 -0700185 * set the root cell information
186 * - can be called with a module parameter string
187 * - can be called from a write to /proc/fs/afs/rootcell
Linus Torvalds1da177e2005-04-16 15:20:36 -0700188 */
189int afs_cell_init(char *rootcell)
190{
191 struct afs_cell *old_root, *new_root;
192 char *cp;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700193
194 _enter("");
195
196 if (!rootcell) {
197 /* module is loaded with no parameters, or built statically.
198 * - in the future we might initialize cell DB here.
199 */
David Howells08e0e7c2007-04-26 15:55:03 -0700200 _leave(" = 0 [no root]");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700201 return 0;
202 }
203
204 cp = strchr(rootcell, ':');
205 if (!cp) {
206 printk(KERN_ERR "kAFS: no VL server IP addresses specified\n");
David Howells08e0e7c2007-04-26 15:55:03 -0700207 _leave(" = -EINVAL");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700208 return -EINVAL;
209 }
210
211 /* allocate a cell record for the root cell */
212 *cp++ = 0;
David Howells08e0e7c2007-04-26 15:55:03 -0700213 new_root = afs_cell_create(rootcell, cp);
214 if (IS_ERR(new_root)) {
215 _leave(" = %ld", PTR_ERR(new_root));
216 return PTR_ERR(new_root);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700217 }
218
David Howells08e0e7c2007-04-26 15:55:03 -0700219 /* install the new cell */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700220 write_lock(&afs_cells_lock);
David Howells08e0e7c2007-04-26 15:55:03 -0700221 old_root = afs_cell_root;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700222 afs_cell_root = new_root;
223 write_unlock(&afs_cells_lock);
David Howells08e0e7c2007-04-26 15:55:03 -0700224 afs_put_cell(old_root);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700225
David Howells08e0e7c2007-04-26 15:55:03 -0700226 _leave(" = 0");
227 return 0;
David Howellsec268152007-04-26 15:49:28 -0700228}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700229
Linus Torvalds1da177e2005-04-16 15:20:36 -0700230/*
231 * lookup a cell record
232 */
David Howells08e0e7c2007-04-26 15:55:03 -0700233struct afs_cell *afs_cell_lookup(const char *name, unsigned namesz)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700234{
235 struct afs_cell *cell;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700236
237 _enter("\"%*.*s\",", namesz, namesz, name ? name : "");
238
David Howells08e0e7c2007-04-26 15:55:03 -0700239 down_read(&afs_cells_sem);
240 read_lock(&afs_cells_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700241
242 if (name) {
243 /* if the cell was named, look for it in the cell record list */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700244 list_for_each_entry(cell, &afs_cells, link) {
245 if (strncmp(cell->name, name, namesz) == 0) {
246 afs_get_cell(cell);
247 goto found;
248 }
249 }
David Howells08e0e7c2007-04-26 15:55:03 -0700250 cell = ERR_PTR(-ENOENT);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700251 found:
David Howells08e0e7c2007-04-26 15:55:03 -0700252 ;
David Howellsec268152007-04-26 15:49:28 -0700253 } else {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700254 cell = afs_cell_root;
255 if (!cell) {
256 /* this should not happen unless user tries to mount
257 * when root cell is not set. Return an impossibly
258 * bizzare errno to alert the user. Things like
259 * ENOENT might be "more appropriate" but they happen
260 * for other reasons.
261 */
David Howells08e0e7c2007-04-26 15:55:03 -0700262 cell = ERR_PTR(-EDESTADDRREQ);
David Howellsec268152007-04-26 15:49:28 -0700263 } else {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700264 afs_get_cell(cell);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700265 }
266
Linus Torvalds1da177e2005-04-16 15:20:36 -0700267 }
268
David Howells08e0e7c2007-04-26 15:55:03 -0700269 read_unlock(&afs_cells_lock);
270 up_read(&afs_cells_sem);
271 _leave(" = %p", cell);
272 return cell;
David Howellsec268152007-04-26 15:49:28 -0700273}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700274
Adrian Bunkc1206a22007-10-16 23:26:41 -0700275#if 0
Linus Torvalds1da177e2005-04-16 15:20:36 -0700276/*
277 * try and get a cell record
278 */
David Howells08e0e7c2007-04-26 15:55:03 -0700279struct afs_cell *afs_get_cell_maybe(struct afs_cell *cell)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700280{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700281 write_lock(&afs_cells_lock);
282
Linus Torvalds1da177e2005-04-16 15:20:36 -0700283 if (cell && !list_empty(&cell->link))
284 afs_get_cell(cell);
285 else
286 cell = NULL;
287
288 write_unlock(&afs_cells_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700289 return cell;
David Howellsec268152007-04-26 15:49:28 -0700290}
Adrian Bunkc1206a22007-10-16 23:26:41 -0700291#endif /* 0 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700292
Linus Torvalds1da177e2005-04-16 15:20:36 -0700293/*
294 * destroy a cell record
295 */
296void afs_put_cell(struct afs_cell *cell)
297{
298 if (!cell)
299 return;
300
301 _enter("%p{%d,%s}", cell, atomic_read(&cell->usage), cell->name);
302
David Howells08e0e7c2007-04-26 15:55:03 -0700303 ASSERTCMP(atomic_read(&cell->usage), >, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700304
305 /* to prevent a race, the decrement and the dequeue must be effectively
306 * atomic */
307 write_lock(&afs_cells_lock);
308
309 if (likely(!atomic_dec_and_test(&cell->usage))) {
310 write_unlock(&afs_cells_lock);
311 _leave("");
312 return;
313 }
314
David Howells08e0e7c2007-04-26 15:55:03 -0700315 ASSERT(list_empty(&cell->servers));
316 ASSERT(list_empty(&cell->vl_list));
317
Linus Torvalds1da177e2005-04-16 15:20:36 -0700318 write_unlock(&afs_cells_lock);
319
David Howells08e0e7c2007-04-26 15:55:03 -0700320 wake_up(&afs_cells_freeable_wq);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700321
322 _leave(" [unused]");
David Howellsec268152007-04-26 15:49:28 -0700323}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700324
Linus Torvalds1da177e2005-04-16 15:20:36 -0700325/*
326 * destroy a cell record
David Howells08e0e7c2007-04-26 15:55:03 -0700327 * - must be called with the afs_cells_sem write-locked
328 * - cell->link should have been broken by the caller
Linus Torvalds1da177e2005-04-16 15:20:36 -0700329 */
330static void afs_cell_destroy(struct afs_cell *cell)
331{
332 _enter("%p{%d,%s}", cell, atomic_read(&cell->usage), cell->name);
333
David Howells08e0e7c2007-04-26 15:55:03 -0700334 ASSERTCMP(atomic_read(&cell->usage), >=, 0);
335 ASSERT(list_empty(&cell->link));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700336
David Howells08e0e7c2007-04-26 15:55:03 -0700337 /* wait for everyone to stop using the cell */
338 if (atomic_read(&cell->usage) > 0) {
339 DECLARE_WAITQUEUE(myself, current);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700340
David Howells08e0e7c2007-04-26 15:55:03 -0700341 _debug("wait for cell %s", cell->name);
342 set_current_state(TASK_UNINTERRUPTIBLE);
343 add_wait_queue(&afs_cells_freeable_wq, &myself);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700344
David Howells08e0e7c2007-04-26 15:55:03 -0700345 while (atomic_read(&cell->usage) > 0) {
346 schedule();
347 set_current_state(TASK_UNINTERRUPTIBLE);
348 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700349
David Howells08e0e7c2007-04-26 15:55:03 -0700350 remove_wait_queue(&afs_cells_freeable_wq, &myself);
351 set_current_state(TASK_RUNNING);
352 }
353
354 _debug("cell dead");
355 ASSERTCMP(atomic_read(&cell->usage), ==, 0);
356 ASSERT(list_empty(&cell->servers));
357 ASSERT(list_empty(&cell->vl_list));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700358
359 afs_proc_cell_remove(cell);
360
361 down_write(&afs_proc_cells_sem);
362 list_del_init(&cell->proc_link);
363 up_write(&afs_proc_cells_sem);
364
365#ifdef AFS_CACHING_SUPPORT
366 cachefs_relinquish_cookie(cell->cache, 0);
367#endif
368
David Howells00d3b7a2007-04-26 15:57:07 -0700369 key_put(cell->anonymous_key);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700370 kfree(cell);
371
372 _leave(" [destroyed]");
David Howellsec268152007-04-26 15:49:28 -0700373}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700374
Linus Torvalds1da177e2005-04-16 15:20:36 -0700375/*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700376 * purge in-memory cell database on module unload or afs_init() failure
377 * - the timeout daemon is stopped before calling this
378 */
379void afs_cell_purge(void)
380{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700381 struct afs_cell *cell;
382
383 _enter("");
384
385 afs_put_cell(afs_cell_root);
386
David Howells08e0e7c2007-04-26 15:55:03 -0700387 down_write(&afs_cells_sem);
388
Linus Torvalds1da177e2005-04-16 15:20:36 -0700389 while (!list_empty(&afs_cells)) {
390 cell = NULL;
391
392 /* remove the next cell from the front of the list */
393 write_lock(&afs_cells_lock);
394
395 if (!list_empty(&afs_cells)) {
396 cell = list_entry(afs_cells.next,
397 struct afs_cell, link);
398 list_del_init(&cell->link);
399 }
400
401 write_unlock(&afs_cells_lock);
402
403 if (cell) {
404 _debug("PURGING CELL %s (%d)",
405 cell->name, atomic_read(&cell->usage));
406
Linus Torvalds1da177e2005-04-16 15:20:36 -0700407 /* now the cell should be left with no references */
408 afs_cell_destroy(cell);
409 }
410 }
411
David Howells08e0e7c2007-04-26 15:55:03 -0700412 up_write(&afs_cells_sem);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700413 _leave("");
David Howellsec268152007-04-26 15:49:28 -0700414}