Commit | Line | Data |
---|---|---|
08e0e7c8 | 1 | /* AFS volume location management |
1da177e4 | 2 | * |
08e0e7c8 | 3 | * Copyright (C) 2002, 2007 Red Hat, Inc. All Rights Reserved. |
1da177e4 LT |
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/kernel.h> | |
13 | #include <linux/module.h> | |
14 | #include <linux/init.h> | |
e8edc6e0 | 15 | #include <linux/sched.h> |
1da177e4 LT |
16 | #include "internal.h" |
17 | ||
c1206a2c AB |
18 | static unsigned afs_vlocation_timeout = 10; /* volume location timeout in seconds */ |
19 | static unsigned afs_vlocation_update_timeout = 10 * 60; | |
1da177e4 | 20 | |
08e0e7c8 DH |
21 | static void afs_vlocation_reaper(struct work_struct *); |
22 | static void afs_vlocation_updater(struct work_struct *); | |
1da177e4 | 23 | |
08e0e7c8 DH |
24 | static LIST_HEAD(afs_vlocation_updates); |
25 | static LIST_HEAD(afs_vlocation_graveyard); | |
26 | static DEFINE_SPINLOCK(afs_vlocation_updates_lock); | |
27 | static DEFINE_SPINLOCK(afs_vlocation_graveyard_lock); | |
28 | static DECLARE_DELAYED_WORK(afs_vlocation_reap, afs_vlocation_reaper); | |
29 | static DECLARE_DELAYED_WORK(afs_vlocation_update, afs_vlocation_updater); | |
30 | static struct workqueue_struct *afs_vlocation_update_worker; | |
1da177e4 | 31 | |
1da177e4 LT |
32 | /* |
33 | * iterate through the VL servers in a cell until one of them admits knowing | |
34 | * about the volume in question | |
1da177e4 | 35 | */ |
08e0e7c8 | 36 | static int afs_vlocation_access_vl_by_name(struct afs_vlocation *vl, |
00d3b7a4 | 37 | struct key *key, |
1da177e4 LT |
38 | struct afs_cache_vlocation *vldb) |
39 | { | |
08e0e7c8 DH |
40 | struct afs_cell *cell = vl->cell; |
41 | struct in_addr addr; | |
1da177e4 LT |
42 | int count, ret; |
43 | ||
08e0e7c8 | 44 | _enter("%s,%s", cell->name, vl->vldb.name); |
1da177e4 | 45 | |
08e0e7c8 | 46 | down_write(&vl->cell->vl_sem); |
1da177e4 LT |
47 | ret = -ENOMEDIUM; |
48 | for (count = cell->vl_naddrs; count > 0; count--) { | |
08e0e7c8 DH |
49 | addr = cell->vl_addrs[cell->vl_curr_svix]; |
50 | ||
51 | _debug("CellServ[%hu]: %08x", cell->vl_curr_svix, addr.s_addr); | |
1da177e4 LT |
52 | |
53 | /* attempt to access the VL server */ | |
00d3b7a4 | 54 | ret = afs_vl_get_entry_by_name(&addr, key, vl->vldb.name, vldb, |
08e0e7c8 | 55 | &afs_sync_call); |
1da177e4 LT |
56 | switch (ret) { |
57 | case 0: | |
1da177e4 LT |
58 | goto out; |
59 | case -ENOMEM: | |
60 | case -ENONET: | |
61 | case -ENETUNREACH: | |
62 | case -EHOSTUNREACH: | |
63 | case -ECONNREFUSED: | |
1da177e4 LT |
64 | if (ret == -ENOMEM || ret == -ENONET) |
65 | goto out; | |
66 | goto rotate; | |
67 | case -ENOMEDIUM: | |
1da177e4 LT |
68 | goto out; |
69 | default: | |
08e0e7c8 | 70 | ret = -EIO; |
1da177e4 LT |
71 | goto rotate; |
72 | } | |
73 | ||
74 | /* rotate the server records upon lookup failure */ | |
75 | rotate: | |
76 | cell->vl_curr_svix++; | |
77 | cell->vl_curr_svix %= cell->vl_naddrs; | |
78 | } | |
79 | ||
ec26815a | 80 | out: |
08e0e7c8 | 81 | up_write(&vl->cell->vl_sem); |
1da177e4 LT |
82 | _leave(" = %d", ret); |
83 | return ret; | |
ec26815a | 84 | } |
1da177e4 | 85 | |
1da177e4 LT |
86 | /* |
87 | * iterate through the VL servers in a cell until one of them admits knowing | |
88 | * about the volume in question | |
1da177e4 | 89 | */ |
08e0e7c8 | 90 | static int afs_vlocation_access_vl_by_id(struct afs_vlocation *vl, |
00d3b7a4 | 91 | struct key *key, |
1da177e4 LT |
92 | afs_volid_t volid, |
93 | afs_voltype_t voltype, | |
94 | struct afs_cache_vlocation *vldb) | |
95 | { | |
08e0e7c8 DH |
96 | struct afs_cell *cell = vl->cell; |
97 | struct in_addr addr; | |
1da177e4 LT |
98 | int count, ret; |
99 | ||
100 | _enter("%s,%x,%d,", cell->name, volid, voltype); | |
101 | ||
08e0e7c8 | 102 | down_write(&vl->cell->vl_sem); |
1da177e4 LT |
103 | ret = -ENOMEDIUM; |
104 | for (count = cell->vl_naddrs; count > 0; count--) { | |
08e0e7c8 DH |
105 | addr = cell->vl_addrs[cell->vl_curr_svix]; |
106 | ||
107 | _debug("CellServ[%hu]: %08x", cell->vl_curr_svix, addr.s_addr); | |
1da177e4 LT |
108 | |
109 | /* attempt to access the VL server */ | |
00d3b7a4 | 110 | ret = afs_vl_get_entry_by_id(&addr, key, volid, voltype, vldb, |
08e0e7c8 | 111 | &afs_sync_call); |
1da177e4 LT |
112 | switch (ret) { |
113 | case 0: | |
1da177e4 LT |
114 | goto out; |
115 | case -ENOMEM: | |
116 | case -ENONET: | |
117 | case -ENETUNREACH: | |
118 | case -EHOSTUNREACH: | |
119 | case -ECONNREFUSED: | |
1da177e4 LT |
120 | if (ret == -ENOMEM || ret == -ENONET) |
121 | goto out; | |
122 | goto rotate; | |
08e0e7c8 DH |
123 | case -EBUSY: |
124 | vl->upd_busy_cnt++; | |
125 | if (vl->upd_busy_cnt <= 3) { | |
126 | if (vl->upd_busy_cnt > 1) { | |
127 | /* second+ BUSY - sleep a little bit */ | |
128 | set_current_state(TASK_UNINTERRUPTIBLE); | |
129 | schedule_timeout(1); | |
130 | __set_current_state(TASK_RUNNING); | |
131 | } | |
132 | continue; | |
133 | } | |
134 | break; | |
1da177e4 | 135 | case -ENOMEDIUM: |
08e0e7c8 DH |
136 | vl->upd_rej_cnt++; |
137 | goto rotate; | |
1da177e4 | 138 | default: |
08e0e7c8 | 139 | ret = -EIO; |
1da177e4 LT |
140 | goto rotate; |
141 | } | |
142 | ||
143 | /* rotate the server records upon lookup failure */ | |
144 | rotate: | |
145 | cell->vl_curr_svix++; | |
146 | cell->vl_curr_svix %= cell->vl_naddrs; | |
08e0e7c8 | 147 | vl->upd_busy_cnt = 0; |
1da177e4 LT |
148 | } |
149 | ||
ec26815a | 150 | out: |
08e0e7c8 DH |
151 | if (ret < 0 && vl->upd_rej_cnt > 0) { |
152 | printk(KERN_NOTICE "kAFS:" | |
153 | " Active volume no longer valid '%s'\n", | |
154 | vl->vldb.name); | |
155 | vl->valid = 0; | |
156 | ret = -ENOMEDIUM; | |
157 | } | |
158 | ||
159 | up_write(&vl->cell->vl_sem); | |
1da177e4 LT |
160 | _leave(" = %d", ret); |
161 | return ret; | |
ec26815a | 162 | } |
1da177e4 | 163 | |
1da177e4 | 164 | /* |
08e0e7c8 | 165 | * allocate a volume location record |
1da177e4 | 166 | */ |
08e0e7c8 DH |
167 | static struct afs_vlocation *afs_vlocation_alloc(struct afs_cell *cell, |
168 | const char *name, | |
169 | size_t namesz) | |
1da177e4 | 170 | { |
08e0e7c8 DH |
171 | struct afs_vlocation *vl; |
172 | ||
173 | vl = kzalloc(sizeof(struct afs_vlocation), GFP_KERNEL); | |
174 | if (vl) { | |
175 | vl->cell = cell; | |
176 | vl->state = AFS_VL_NEW; | |
177 | atomic_set(&vl->usage, 1); | |
178 | INIT_LIST_HEAD(&vl->link); | |
179 | INIT_LIST_HEAD(&vl->grave); | |
180 | INIT_LIST_HEAD(&vl->update); | |
181 | init_waitqueue_head(&vl->waitq); | |
39bf0949 | 182 | spin_lock_init(&vl->lock); |
08e0e7c8 | 183 | memcpy(vl->vldb.name, name, namesz); |
1da177e4 LT |
184 | } |
185 | ||
08e0e7c8 DH |
186 | _leave(" = %p", vl); |
187 | return vl; | |
188 | } | |
1da177e4 | 189 | |
08e0e7c8 DH |
190 | /* |
191 | * update record if we found it in the cache | |
192 | */ | |
193 | static int afs_vlocation_update_record(struct afs_vlocation *vl, | |
00d3b7a4 | 194 | struct key *key, |
08e0e7c8 DH |
195 | struct afs_cache_vlocation *vldb) |
196 | { | |
197 | afs_voltype_t voltype; | |
198 | afs_volid_t vid; | |
199 | int ret; | |
1da177e4 | 200 | |
1da177e4 | 201 | /* try to look up a cached volume in the cell VL databases by ID */ |
1da177e4 | 202 | _debug("Locally Cached: %s %02x { %08x(%x) %08x(%x) %08x(%x) }", |
08e0e7c8 DH |
203 | vl->vldb.name, |
204 | vl->vldb.vidmask, | |
205 | ntohl(vl->vldb.servers[0].s_addr), | |
206 | vl->vldb.srvtmask[0], | |
207 | ntohl(vl->vldb.servers[1].s_addr), | |
208 | vl->vldb.srvtmask[1], | |
209 | ntohl(vl->vldb.servers[2].s_addr), | |
210 | vl->vldb.srvtmask[2]); | |
1da177e4 LT |
211 | |
212 | _debug("Vids: %08x %08x %08x", | |
08e0e7c8 DH |
213 | vl->vldb.vid[0], |
214 | vl->vldb.vid[1], | |
215 | vl->vldb.vid[2]); | |
1da177e4 | 216 | |
08e0e7c8 DH |
217 | if (vl->vldb.vidmask & AFS_VOL_VTM_RW) { |
218 | vid = vl->vldb.vid[0]; | |
1da177e4 | 219 | voltype = AFSVL_RWVOL; |
08e0e7c8 DH |
220 | } else if (vl->vldb.vidmask & AFS_VOL_VTM_RO) { |
221 | vid = vl->vldb.vid[1]; | |
1da177e4 | 222 | voltype = AFSVL_ROVOL; |
08e0e7c8 DH |
223 | } else if (vl->vldb.vidmask & AFS_VOL_VTM_BAK) { |
224 | vid = vl->vldb.vid[2]; | |
1da177e4 | 225 | voltype = AFSVL_BACKVOL; |
ec26815a | 226 | } else { |
1da177e4 LT |
227 | BUG(); |
228 | vid = 0; | |
229 | voltype = 0; | |
230 | } | |
231 | ||
08e0e7c8 DH |
232 | /* contact the server to make sure the volume is still available |
233 | * - TODO: need to handle disconnected operation here | |
234 | */ | |
00d3b7a4 | 235 | ret = afs_vlocation_access_vl_by_id(vl, key, vid, voltype, vldb); |
1da177e4 LT |
236 | switch (ret) { |
237 | /* net error */ | |
238 | default: | |
08e0e7c8 DH |
239 | printk(KERN_WARNING "kAFS:" |
240 | " failed to update volume '%s' (%x) up in '%s': %d\n", | |
241 | vl->vldb.name, vid, vl->cell->name, ret); | |
242 | _leave(" = %d", ret); | |
243 | return ret; | |
1da177e4 LT |
244 | |
245 | /* pulled from local cache into memory */ | |
246 | case 0: | |
08e0e7c8 DH |
247 | _leave(" = 0"); |
248 | return 0; | |
1da177e4 LT |
249 | |
250 | /* uh oh... looks like the volume got deleted */ | |
251 | case -ENOMEDIUM: | |
08e0e7c8 DH |
252 | printk(KERN_ERR "kAFS:" |
253 | " volume '%s' (%x) does not exist '%s'\n", | |
254 | vl->vldb.name, vid, vl->cell->name); | |
1da177e4 LT |
255 | |
256 | /* TODO: make existing record unavailable */ | |
08e0e7c8 DH |
257 | _leave(" = %d", ret); |
258 | return ret; | |
1da177e4 | 259 | } |
08e0e7c8 | 260 | } |
1da177e4 | 261 | |
08e0e7c8 DH |
262 | /* |
263 | * apply the update to a VL record | |
264 | */ | |
265 | static void afs_vlocation_apply_update(struct afs_vlocation *vl, | |
266 | struct afs_cache_vlocation *vldb) | |
267 | { | |
268 | _debug("Done VL Lookup: %s %02x { %08x(%x) %08x(%x) %08x(%x) }", | |
269 | vldb->name, vldb->vidmask, | |
270 | ntohl(vldb->servers[0].s_addr), vldb->srvtmask[0], | |
271 | ntohl(vldb->servers[1].s_addr), vldb->srvtmask[1], | |
272 | ntohl(vldb->servers[2].s_addr), vldb->srvtmask[2]); | |
1da177e4 | 273 | |
08e0e7c8 DH |
274 | _debug("Vids: %08x %08x %08x", |
275 | vldb->vid[0], vldb->vid[1], vldb->vid[2]); | |
1da177e4 | 276 | |
08e0e7c8 DH |
277 | if (strcmp(vldb->name, vl->vldb.name) != 0) |
278 | printk(KERN_NOTICE "kAFS:" | |
279 | " name of volume '%s' changed to '%s' on server\n", | |
280 | vl->vldb.name, vldb->name); | |
1da177e4 | 281 | |
08e0e7c8 | 282 | vl->vldb = *vldb; |
1da177e4 | 283 | |
9b3f26c9 DH |
284 | #ifdef CONFIG_AFS_FSCACHE |
285 | fscache_update_cookie(vl->cache); | |
1da177e4 | 286 | #endif |
ec26815a | 287 | } |
1da177e4 | 288 | |
1da177e4 | 289 | /* |
08e0e7c8 DH |
290 | * fill in a volume location record, consulting the cache and the VL server |
291 | * both | |
1da177e4 | 292 | */ |
00d3b7a4 DH |
293 | static int afs_vlocation_fill_in_record(struct afs_vlocation *vl, |
294 | struct key *key) | |
1da177e4 | 295 | { |
08e0e7c8 DH |
296 | struct afs_cache_vlocation vldb; |
297 | int ret; | |
1da177e4 | 298 | |
08e0e7c8 | 299 | _enter(""); |
1da177e4 | 300 | |
08e0e7c8 | 301 | ASSERTCMP(vl->valid, ==, 0); |
1da177e4 | 302 | |
08e0e7c8 | 303 | memset(&vldb, 0, sizeof(vldb)); |
1da177e4 | 304 | |
08e0e7c8 | 305 | /* see if we have an in-cache copy (will set vl->valid if there is) */ |
9b3f26c9 DH |
306 | #ifdef CONFIG_AFS_FSCACHE |
307 | vl->cache = fscache_acquire_cookie(vl->cell->cache, | |
308 | &afs_vlocation_cache_index_def, vl); | |
08e0e7c8 | 309 | #endif |
1da177e4 | 310 | |
08e0e7c8 DH |
311 | if (vl->valid) { |
312 | /* try to update a known volume in the cell VL databases by | |
313 | * ID as the name may have changed */ | |
314 | _debug("found in cache"); | |
00d3b7a4 | 315 | ret = afs_vlocation_update_record(vl, key, &vldb); |
08e0e7c8 DH |
316 | } else { |
317 | /* try to look up an unknown volume in the cell VL databases by | |
318 | * name */ | |
00d3b7a4 | 319 | ret = afs_vlocation_access_vl_by_name(vl, key, &vldb); |
08e0e7c8 DH |
320 | if (ret < 0) { |
321 | printk("kAFS: failed to locate '%s' in cell '%s'\n", | |
322 | vl->vldb.name, vl->cell->name); | |
323 | return ret; | |
324 | } | |
1da177e4 LT |
325 | } |
326 | ||
08e0e7c8 DH |
327 | afs_vlocation_apply_update(vl, &vldb); |
328 | _leave(" = 0"); | |
329 | return 0; | |
ec26815a | 330 | } |
1da177e4 | 331 | |
1da177e4 | 332 | /* |
08e0e7c8 | 333 | * queue a vlocation record for updates |
1da177e4 | 334 | */ |
c1206a2c | 335 | static void afs_vlocation_queue_for_updates(struct afs_vlocation *vl) |
1da177e4 | 336 | { |
08e0e7c8 | 337 | struct afs_vlocation *xvl; |
1da177e4 | 338 | |
08e0e7c8 DH |
339 | /* wait at least 10 minutes before updating... */ |
340 | vl->update_at = get_seconds() + afs_vlocation_update_timeout; | |
341 | ||
342 | spin_lock(&afs_vlocation_updates_lock); | |
343 | ||
344 | if (!list_empty(&afs_vlocation_updates)) { | |
345 | /* ... but wait at least 1 second more than the newest record | |
346 | * already queued so that we don't spam the VL server suddenly | |
347 | * with lots of requests | |
348 | */ | |
349 | xvl = list_entry(afs_vlocation_updates.prev, | |
350 | struct afs_vlocation, update); | |
351 | if (vl->update_at <= xvl->update_at) | |
352 | vl->update_at = xvl->update_at + 1; | |
353 | } else { | |
354 | queue_delayed_work(afs_vlocation_update_worker, | |
355 | &afs_vlocation_update, | |
356 | afs_vlocation_update_timeout * HZ); | |
1da177e4 | 357 | } |
08e0e7c8 DH |
358 | |
359 | list_add_tail(&vl->update, &afs_vlocation_updates); | |
360 | spin_unlock(&afs_vlocation_updates_lock); | |
ec26815a | 361 | } |
1da177e4 | 362 | |
1da177e4 | 363 | /* |
08e0e7c8 DH |
364 | * lookup volume location |
365 | * - iterate through the VL servers in a cell until one of them admits knowing | |
366 | * about the volume in question | |
367 | * - lookup in the local cache if not able to find on the VL server | |
368 | * - insert/update in the local cache if did get a VL response | |
1da177e4 | 369 | */ |
08e0e7c8 | 370 | struct afs_vlocation *afs_vlocation_lookup(struct afs_cell *cell, |
00d3b7a4 | 371 | struct key *key, |
08e0e7c8 DH |
372 | const char *name, |
373 | size_t namesz) | |
1da177e4 | 374 | { |
08e0e7c8 DH |
375 | struct afs_vlocation *vl; |
376 | int ret; | |
1da177e4 | 377 | |
00d3b7a4 DH |
378 | _enter("{%s},{%x},%*.*s,%zu", |
379 | cell->name, key_serial(key), | |
380 | (int) namesz, (int) namesz, name, namesz); | |
1da177e4 | 381 | |
6551198a | 382 | if (namesz >= sizeof(vl->vldb.name)) { |
08e0e7c8 DH |
383 | _leave(" = -ENAMETOOLONG"); |
384 | return ERR_PTR(-ENAMETOOLONG); | |
385 | } | |
1da177e4 | 386 | |
08e0e7c8 DH |
387 | /* see if we have an in-memory copy first */ |
388 | down_write(&cell->vl_sem); | |
389 | spin_lock(&cell->vl_lock); | |
390 | list_for_each_entry(vl, &cell->vl_list, link) { | |
391 | if (vl->vldb.name[namesz] != '\0') | |
392 | continue; | |
393 | if (memcmp(vl->vldb.name, name, namesz) == 0) | |
394 | goto found_in_memory; | |
1da177e4 | 395 | } |
08e0e7c8 | 396 | spin_unlock(&cell->vl_lock); |
1da177e4 | 397 | |
08e0e7c8 DH |
398 | /* not in the cell's in-memory lists - create a new record */ |
399 | vl = afs_vlocation_alloc(cell, name, namesz); | |
400 | if (!vl) { | |
401 | up_write(&cell->vl_sem); | |
402 | return ERR_PTR(-ENOMEM); | |
403 | } | |
1da177e4 | 404 | |
08e0e7c8 | 405 | afs_get_cell(cell); |
1da177e4 | 406 | |
08e0e7c8 DH |
407 | list_add_tail(&vl->link, &cell->vl_list); |
408 | vl->state = AFS_VL_CREATING; | |
409 | up_write(&cell->vl_sem); | |
1da177e4 | 410 | |
08e0e7c8 | 411 | fill_in_record: |
00d3b7a4 | 412 | ret = afs_vlocation_fill_in_record(vl, key); |
08e0e7c8 DH |
413 | if (ret < 0) |
414 | goto error_abandon; | |
39bf0949 | 415 | spin_lock(&vl->lock); |
08e0e7c8 | 416 | vl->state = AFS_VL_VALID; |
39bf0949 | 417 | spin_unlock(&vl->lock); |
47051a21 | 418 | wake_up(&vl->waitq); |
1da177e4 | 419 | |
9b3f26c9 DH |
420 | /* update volume entry in local cache */ |
421 | #ifdef CONFIG_AFS_FSCACHE | |
422 | fscache_update_cookie(vl->cache); | |
423 | #endif | |
424 | ||
08e0e7c8 DH |
425 | /* schedule for regular updates */ |
426 | afs_vlocation_queue_for_updates(vl); | |
427 | goto success; | |
1da177e4 | 428 | |
08e0e7c8 DH |
429 | found_in_memory: |
430 | /* found in memory */ | |
431 | _debug("found in memory"); | |
432 | atomic_inc(&vl->usage); | |
433 | spin_unlock(&cell->vl_lock); | |
434 | if (!list_empty(&vl->grave)) { | |
435 | spin_lock(&afs_vlocation_graveyard_lock); | |
436 | list_del_init(&vl->grave); | |
437 | spin_unlock(&afs_vlocation_graveyard_lock); | |
1da177e4 | 438 | } |
08e0e7c8 | 439 | up_write(&cell->vl_sem); |
1da177e4 | 440 | |
08e0e7c8 | 441 | /* see if it was an abandoned record that we might try filling in */ |
39bf0949 | 442 | spin_lock(&vl->lock); |
08e0e7c8 DH |
443 | while (vl->state != AFS_VL_VALID) { |
444 | afs_vlocation_state_t state = vl->state; | |
1da177e4 | 445 | |
08e0e7c8 | 446 | _debug("invalid [state %d]", state); |
1da177e4 | 447 | |
47051a21 | 448 | if (state == AFS_VL_NEW || state == AFS_VL_NO_VOLUME) { |
39bf0949 DM |
449 | vl->state = AFS_VL_CREATING; |
450 | spin_unlock(&vl->lock); | |
451 | goto fill_in_record; | |
08e0e7c8 DH |
452 | } |
453 | ||
454 | /* must now wait for creation or update by someone else to | |
455 | * complete */ | |
456 | _debug("wait"); | |
457 | ||
39bf0949 | 458 | spin_unlock(&vl->lock); |
47051a21 DH |
459 | ret = wait_event_interruptible(vl->waitq, |
460 | vl->state == AFS_VL_NEW || | |
461 | vl->state == AFS_VL_VALID || | |
462 | vl->state == AFS_VL_NO_VOLUME); | |
08e0e7c8 DH |
463 | if (ret < 0) |
464 | goto error; | |
39bf0949 | 465 | spin_lock(&vl->lock); |
1da177e4 | 466 | } |
39bf0949 | 467 | spin_unlock(&vl->lock); |
1da177e4 | 468 | |
08e0e7c8 | 469 | success: |
9b3f26c9 | 470 | _leave(" = %p", vl); |
08e0e7c8 DH |
471 | return vl; |
472 | ||
473 | error_abandon: | |
39bf0949 | 474 | spin_lock(&vl->lock); |
08e0e7c8 | 475 | vl->state = AFS_VL_NEW; |
39bf0949 | 476 | spin_unlock(&vl->lock); |
47051a21 | 477 | wake_up(&vl->waitq); |
08e0e7c8 DH |
478 | error: |
479 | ASSERT(vl != NULL); | |
480 | afs_put_vlocation(vl); | |
1da177e4 | 481 | _leave(" = %d", ret); |
08e0e7c8 | 482 | return ERR_PTR(ret); |
ec26815a | 483 | } |
1da177e4 | 484 | |
1da177e4 | 485 | /* |
08e0e7c8 | 486 | * finish using a volume location record |
1da177e4 | 487 | */ |
08e0e7c8 | 488 | void afs_put_vlocation(struct afs_vlocation *vl) |
1da177e4 | 489 | { |
08e0e7c8 DH |
490 | if (!vl) |
491 | return; | |
1da177e4 | 492 | |
08e0e7c8 | 493 | _enter("%s", vl->vldb.name); |
1da177e4 | 494 | |
08e0e7c8 | 495 | ASSERTCMP(atomic_read(&vl->usage), >, 0); |
1da177e4 | 496 | |
08e0e7c8 DH |
497 | if (likely(!atomic_dec_and_test(&vl->usage))) { |
498 | _leave(""); | |
499 | return; | |
500 | } | |
1da177e4 | 501 | |
08e0e7c8 DH |
502 | spin_lock(&afs_vlocation_graveyard_lock); |
503 | if (atomic_read(&vl->usage) == 0) { | |
504 | _debug("buried"); | |
505 | list_move_tail(&vl->grave, &afs_vlocation_graveyard); | |
506 | vl->time_of_death = get_seconds(); | |
507 | schedule_delayed_work(&afs_vlocation_reap, | |
508 | afs_vlocation_timeout * HZ); | |
509 | ||
510 | /* suspend updates on this record */ | |
511 | if (!list_empty(&vl->update)) { | |
512 | spin_lock(&afs_vlocation_updates_lock); | |
513 | list_del_init(&vl->update); | |
514 | spin_unlock(&afs_vlocation_updates_lock); | |
515 | } | |
516 | } | |
517 | spin_unlock(&afs_vlocation_graveyard_lock); | |
518 | _leave(" [killed?]"); | |
ec26815a | 519 | } |
1da177e4 | 520 | |
1da177e4 | 521 | /* |
08e0e7c8 | 522 | * destroy a dead volume location record |
1da177e4 | 523 | */ |
08e0e7c8 | 524 | static void afs_vlocation_destroy(struct afs_vlocation *vl) |
1da177e4 | 525 | { |
08e0e7c8 | 526 | _enter("%p", vl); |
1da177e4 | 527 | |
9b3f26c9 DH |
528 | #ifdef CONFIG_AFS_FSCACHE |
529 | fscache_relinquish_cookie(vl->cache, 0); | |
08e0e7c8 | 530 | #endif |
08e0e7c8 DH |
531 | afs_put_cell(vl->cell); |
532 | kfree(vl); | |
533 | } | |
534 | ||
535 | /* | |
536 | * reap dead volume location records | |
537 | */ | |
538 | static void afs_vlocation_reaper(struct work_struct *work) | |
539 | { | |
540 | LIST_HEAD(corpses); | |
541 | struct afs_vlocation *vl; | |
542 | unsigned long delay, expiry; | |
543 | time_t now; | |
1da177e4 | 544 | |
08e0e7c8 | 545 | _enter(""); |
1da177e4 | 546 | |
08e0e7c8 DH |
547 | now = get_seconds(); |
548 | spin_lock(&afs_vlocation_graveyard_lock); | |
549 | ||
550 | while (!list_empty(&afs_vlocation_graveyard)) { | |
551 | vl = list_entry(afs_vlocation_graveyard.next, | |
552 | struct afs_vlocation, grave); | |
553 | ||
554 | _debug("check %p", vl); | |
555 | ||
556 | /* the queue is ordered most dead first */ | |
557 | expiry = vl->time_of_death + afs_vlocation_timeout; | |
558 | if (expiry > now) { | |
559 | delay = (expiry - now) * HZ; | |
560 | _debug("delay %lu", delay); | |
561 | if (!schedule_delayed_work(&afs_vlocation_reap, | |
562 | delay)) { | |
563 | cancel_delayed_work(&afs_vlocation_reap); | |
564 | schedule_delayed_work(&afs_vlocation_reap, | |
565 | delay); | |
566 | } | |
567 | break; | |
568 | } | |
1da177e4 | 569 | |
08e0e7c8 DH |
570 | spin_lock(&vl->cell->vl_lock); |
571 | if (atomic_read(&vl->usage) > 0) { | |
572 | _debug("no reap"); | |
573 | list_del_init(&vl->grave); | |
ec26815a | 574 | } else { |
08e0e7c8 DH |
575 | _debug("reap"); |
576 | list_move_tail(&vl->grave, &corpses); | |
577 | list_del_init(&vl->link); | |
1da177e4 | 578 | } |
08e0e7c8 | 579 | spin_unlock(&vl->cell->vl_lock); |
1da177e4 LT |
580 | } |
581 | ||
08e0e7c8 | 582 | spin_unlock(&afs_vlocation_graveyard_lock); |
1da177e4 | 583 | |
08e0e7c8 DH |
584 | /* now reap the corpses we've extracted */ |
585 | while (!list_empty(&corpses)) { | |
586 | vl = list_entry(corpses.next, struct afs_vlocation, grave); | |
587 | list_del(&vl->grave); | |
588 | afs_vlocation_destroy(vl); | |
1da177e4 LT |
589 | } |
590 | ||
591 | _leave(""); | |
08e0e7c8 | 592 | } |
1da177e4 | 593 | |
08e0e7c8 DH |
594 | /* |
595 | * initialise the VL update process | |
596 | */ | |
597 | int __init afs_vlocation_update_init(void) | |
598 | { | |
599 | afs_vlocation_update_worker = | |
600 | create_singlethread_workqueue("kafs_vlupdated"); | |
601 | return afs_vlocation_update_worker ? 0 : -ENOMEM; | |
602 | } | |
603 | ||
604 | /* | |
605 | * discard all the volume location records for rmmod | |
606 | */ | |
fbb3fcba | 607 | void afs_vlocation_purge(void) |
08e0e7c8 DH |
608 | { |
609 | afs_vlocation_timeout = 0; | |
610 | ||
611 | spin_lock(&afs_vlocation_updates_lock); | |
612 | list_del_init(&afs_vlocation_updates); | |
613 | spin_unlock(&afs_vlocation_updates_lock); | |
614 | cancel_delayed_work(&afs_vlocation_update); | |
615 | queue_delayed_work(afs_vlocation_update_worker, | |
616 | &afs_vlocation_update, 0); | |
617 | destroy_workqueue(afs_vlocation_update_worker); | |
618 | ||
619 | cancel_delayed_work(&afs_vlocation_reap); | |
620 | schedule_delayed_work(&afs_vlocation_reap, 0); | |
ec26815a | 621 | } |
1da177e4 | 622 | |
1da177e4 | 623 | /* |
08e0e7c8 | 624 | * update a volume location |
1da177e4 | 625 | */ |
08e0e7c8 | 626 | static void afs_vlocation_updater(struct work_struct *work) |
1da177e4 LT |
627 | { |
628 | struct afs_cache_vlocation vldb; | |
08e0e7c8 DH |
629 | struct afs_vlocation *vl, *xvl; |
630 | time_t now; | |
631 | long timeout; | |
1da177e4 LT |
632 | int ret; |
633 | ||
08e0e7c8 | 634 | _enter(""); |
1da177e4 | 635 | |
08e0e7c8 | 636 | now = get_seconds(); |
1da177e4 | 637 | |
08e0e7c8 DH |
638 | /* find a record to update */ |
639 | spin_lock(&afs_vlocation_updates_lock); | |
640 | for (;;) { | |
641 | if (list_empty(&afs_vlocation_updates)) { | |
642 | spin_unlock(&afs_vlocation_updates_lock); | |
643 | _leave(" [nothing]"); | |
644 | return; | |
645 | } | |
1da177e4 | 646 | |
08e0e7c8 DH |
647 | vl = list_entry(afs_vlocation_updates.next, |
648 | struct afs_vlocation, update); | |
649 | if (atomic_read(&vl->usage) > 0) | |
650 | break; | |
651 | list_del_init(&vl->update); | |
1da177e4 LT |
652 | } |
653 | ||
08e0e7c8 DH |
654 | timeout = vl->update_at - now; |
655 | if (timeout > 0) { | |
656 | queue_delayed_work(afs_vlocation_update_worker, | |
657 | &afs_vlocation_update, timeout * HZ); | |
658 | spin_unlock(&afs_vlocation_updates_lock); | |
659 | _leave(" [nothing]"); | |
1da177e4 LT |
660 | return; |
661 | } | |
662 | ||
08e0e7c8 DH |
663 | list_del_init(&vl->update); |
664 | atomic_inc(&vl->usage); | |
665 | spin_unlock(&afs_vlocation_updates_lock); | |
1da177e4 | 666 | |
08e0e7c8 DH |
667 | /* we can now perform the update */ |
668 | _debug("update %s", vl->vldb.name); | |
669 | vl->state = AFS_VL_UPDATING; | |
670 | vl->upd_rej_cnt = 0; | |
671 | vl->upd_busy_cnt = 0; | |
1da177e4 | 672 | |
00d3b7a4 | 673 | ret = afs_vlocation_update_record(vl, NULL, &vldb); |
39bf0949 | 674 | spin_lock(&vl->lock); |
08e0e7c8 DH |
675 | switch (ret) { |
676 | case 0: | |
677 | afs_vlocation_apply_update(vl, &vldb); | |
678 | vl->state = AFS_VL_VALID; | |
679 | break; | |
680 | case -ENOMEDIUM: | |
681 | vl->state = AFS_VL_VOLUME_DELETED; | |
682 | break; | |
683 | default: | |
684 | vl->state = AFS_VL_UNCERTAIN; | |
685 | break; | |
686 | } | |
39bf0949 | 687 | spin_unlock(&vl->lock); |
47051a21 | 688 | wake_up(&vl->waitq); |
1da177e4 | 689 | |
08e0e7c8 DH |
690 | /* and then reschedule */ |
691 | _debug("reschedule"); | |
692 | vl->update_at = get_seconds() + afs_vlocation_update_timeout; | |
1da177e4 | 693 | |
08e0e7c8 | 694 | spin_lock(&afs_vlocation_updates_lock); |
1da177e4 | 695 | |
08e0e7c8 DH |
696 | if (!list_empty(&afs_vlocation_updates)) { |
697 | /* next update in 10 minutes, but wait at least 1 second more | |
698 | * than the newest record already queued so that we don't spam | |
699 | * the VL server suddenly with lots of requests | |
700 | */ | |
701 | xvl = list_entry(afs_vlocation_updates.prev, | |
702 | struct afs_vlocation, update); | |
703 | if (vl->update_at <= xvl->update_at) | |
704 | vl->update_at = xvl->update_at + 1; | |
705 | xvl = list_entry(afs_vlocation_updates.next, | |
706 | struct afs_vlocation, update); | |
707 | timeout = xvl->update_at - now; | |
708 | if (timeout < 0) | |
709 | timeout = 0; | |
710 | } else { | |
711 | timeout = afs_vlocation_update_timeout; | |
1da177e4 LT |
712 | } |
713 | ||
08e0e7c8 | 714 | ASSERT(list_empty(&vl->update)); |
1da177e4 | 715 | |
08e0e7c8 | 716 | list_add_tail(&vl->update, &afs_vlocation_updates); |
1da177e4 | 717 | |
08e0e7c8 DH |
718 | _debug("timeout %ld", timeout); |
719 | queue_delayed_work(afs_vlocation_update_worker, | |
720 | &afs_vlocation_update, timeout * HZ); | |
721 | spin_unlock(&afs_vlocation_updates_lock); | |
722 | afs_put_vlocation(vl); | |
ec26815a | 723 | } |