diff options
Diffstat (limited to 'drivers/staging/pohmelfs/net.c')
-rw-r--r-- | drivers/staging/pohmelfs/net.c | 1209 |
1 files changed, 1209 insertions, 0 deletions
diff --git a/drivers/staging/pohmelfs/net.c b/drivers/staging/pohmelfs/net.c new file mode 100644 index 00000000000..b2e91862208 --- /dev/null +++ b/drivers/staging/pohmelfs/net.c | |||
@@ -0,0 +1,1209 @@ | |||
1 | /* | ||
2 | * 2007+ Copyright (c) Evgeniy Polyakov <zbr@ioremap.net> | ||
3 | * All rights reserved. | ||
4 | * | ||
5 | * This program is free software; you can redistribute it and/or modify | ||
6 | * it under the terms of the GNU General Public License as published by | ||
7 | * the Free Software Foundation; either version 2 of the License, or | ||
8 | * (at your option) any later version. | ||
9 | * | ||
10 | * This program is distributed in the hope that it will be useful, | ||
11 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | ||
12 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | ||
13 | * GNU General Public License for more details. | ||
14 | */ | ||
15 | |||
16 | #include <linux/fsnotify.h> | ||
17 | #include <linux/jhash.h> | ||
18 | #include <linux/in.h> | ||
19 | #include <linux/in6.h> | ||
20 | #include <linux/kthread.h> | ||
21 | #include <linux/pagemap.h> | ||
22 | #include <linux/poll.h> | ||
23 | #include <linux/slab.h> | ||
24 | #include <linux/swap.h> | ||
25 | #include <linux/syscalls.h> | ||
26 | #include <linux/vmalloc.h> | ||
27 | |||
28 | #include "netfs.h" | ||
29 | |||
30 | /* | ||
31 | * Async machinery lives here. | ||
32 | * All commands being sent to server do _not_ require sync reply, | ||
33 | * instead, if it is really needed, like readdir or readpage, caller | ||
34 | * sleeps waiting for data, which will be placed into provided buffer | ||
35 | * and caller will be awakened. | ||
36 | * | ||
37 | * Every command response can come without some listener. For example | ||
38 | * readdir response will add new objects into cache without appropriate | ||
39 | * request from userspace. This is used in cache coherency. | ||
40 | * | ||
41 | * If object is not found for given data, it is discarded. | ||
42 | * | ||
43 | * All requests are received by dedicated kernel thread. | ||
44 | */ | ||
45 | |||
46 | /* | ||
47 | * Basic network sending/receiving functions. | ||
48 | * Blocked mode is used. | ||
49 | */ | ||
50 | static int netfs_data_recv(struct netfs_state *st, void *buf, u64 size) | ||
51 | { | ||
52 | struct msghdr msg; | ||
53 | struct kvec iov; | ||
54 | int err; | ||
55 | |||
56 | BUG_ON(!size); | ||
57 | |||
58 | iov.iov_base = buf; | ||
59 | iov.iov_len = size; | ||
60 | |||
61 | msg.msg_iov = (struct iovec *)&iov; | ||
62 | msg.msg_iovlen = 1; | ||
63 | msg.msg_name = NULL; | ||
64 | msg.msg_namelen = 0; | ||
65 | msg.msg_control = NULL; | ||
66 | msg.msg_controllen = 0; | ||
67 | msg.msg_flags = MSG_DONTWAIT; | ||
68 | |||
69 | err = kernel_recvmsg(st->socket, &msg, &iov, 1, iov.iov_len, | ||
70 | msg.msg_flags); | ||
71 | if (err <= 0) { | ||
72 | printk("%s: failed to recv data: size: %llu, err: %d.\n", __func__, size, err); | ||
73 | if (err == 0) | ||
74 | err = -ECONNRESET; | ||
75 | } | ||
76 | |||
77 | return err; | ||
78 | } | ||
79 | |||
80 | static int pohmelfs_data_recv(struct netfs_state *st, void *data, unsigned int size) | ||
81 | { | ||
82 | unsigned int revents = 0; | ||
83 | unsigned int err_mask = POLLERR | POLLHUP | POLLRDHUP; | ||
84 | unsigned int mask = err_mask | POLLIN; | ||
85 | int err = 0; | ||
86 | |||
87 | while (size && !err) { | ||
88 | revents = netfs_state_poll(st); | ||
89 | |||
90 | if (!(revents & mask)) { | ||
91 | DEFINE_WAIT(wait); | ||
92 | |||
93 | for (;;) { | ||
94 | prepare_to_wait(&st->thread_wait, &wait, TASK_INTERRUPTIBLE); | ||
95 | if (kthread_should_stop()) | ||
96 | break; | ||
97 | |||
98 | revents = netfs_state_poll(st); | ||
99 | |||
100 | if (revents & mask) | ||
101 | break; | ||
102 | |||
103 | if (signal_pending(current)) | ||
104 | break; | ||
105 | |||
106 | schedule(); | ||
107 | continue; | ||
108 | } | ||
109 | finish_wait(&st->thread_wait, &wait); | ||
110 | } | ||
111 | |||
112 | err = 0; | ||
113 | netfs_state_lock(st); | ||
114 | if (st->socket && (st->read_socket == st->socket) && (revents & POLLIN)) { | ||
115 | err = netfs_data_recv(st, data, size); | ||
116 | if (err > 0) { | ||
117 | data += err; | ||
118 | size -= err; | ||
119 | err = 0; | ||
120 | } else if (err == 0) | ||
121 | err = -ECONNRESET; | ||
122 | } | ||
123 | |||
124 | if (revents & err_mask) { | ||
125 | printk("%s: revents: %x, socket: %p, size: %u, err: %d.\n", | ||
126 | __func__, revents, st->socket, size, err); | ||
127 | err = -ECONNRESET; | ||
128 | } | ||
129 | netfs_state_unlock(st); | ||
130 | |||
131 | if (err < 0) { | ||
132 | if (netfs_state_trylock_send(st)) { | ||
133 | netfs_state_exit(st); | ||
134 | err = netfs_state_init(st); | ||
135 | if (!err) | ||
136 | err = -EAGAIN; | ||
137 | netfs_state_unlock_send(st); | ||
138 | } else { | ||
139 | st->need_reset = 1; | ||
140 | } | ||
141 | } | ||
142 | |||
143 | if (kthread_should_stop()) | ||
144 | err = -ENODEV; | ||
145 | |||
146 | if (err) | ||
147 | printk("%s: socket: %p, read_socket: %p, revents: %x, rev_error: %d, " | ||
148 | "should_stop: %d, size: %u, err: %d.\n", | ||
149 | __func__, st->socket, st->read_socket, | ||
150 | revents, revents & err_mask, kthread_should_stop(), size, err); | ||
151 | } | ||
152 | |||
153 | return err; | ||
154 | } | ||
155 | |||
156 | int pohmelfs_data_recv_and_check(struct netfs_state *st, void *data, unsigned int size) | ||
157 | { | ||
158 | struct netfs_cmd *cmd = &st->cmd; | ||
159 | int err; | ||
160 | |||
161 | err = pohmelfs_data_recv(st, data, size); | ||
162 | if (err) | ||
163 | return err; | ||
164 | |||
165 | return pohmelfs_crypto_process_input_data(&st->eng, cmd->iv, data, NULL, size); | ||
166 | } | ||
167 | |||
168 | /* | ||
169 | * Polling machinery. | ||
170 | */ | ||
171 | |||
172 | struct netfs_poll_helper { | ||
173 | poll_table pt; | ||
174 | struct netfs_state *st; | ||
175 | }; | ||
176 | |||
177 | static int netfs_queue_wake(wait_queue_t *wait, unsigned mode, int sync, void *key) | ||
178 | { | ||
179 | struct netfs_state *st = container_of(wait, struct netfs_state, wait); | ||
180 | |||
181 | wake_up(&st->thread_wait); | ||
182 | return 1; | ||
183 | } | ||
184 | |||
185 | static void netfs_queue_func(struct file *file, wait_queue_head_t *whead, | ||
186 | poll_table *pt) | ||
187 | { | ||
188 | struct netfs_state *st = container_of(pt, struct netfs_poll_helper, pt)->st; | ||
189 | |||
190 | st->whead = whead; | ||
191 | init_waitqueue_func_entry(&st->wait, netfs_queue_wake); | ||
192 | add_wait_queue(whead, &st->wait); | ||
193 | } | ||
194 | |||
195 | static void netfs_poll_exit(struct netfs_state *st) | ||
196 | { | ||
197 | if (st->whead) { | ||
198 | remove_wait_queue(st->whead, &st->wait); | ||
199 | st->whead = NULL; | ||
200 | } | ||
201 | } | ||
202 | |||
203 | static int netfs_poll_init(struct netfs_state *st) | ||
204 | { | ||
205 | struct netfs_poll_helper ph; | ||
206 | |||
207 | ph.st = st; | ||
208 | init_poll_funcptr(&ph.pt, &netfs_queue_func); | ||
209 | |||
210 | st->socket->ops->poll(NULL, st->socket, &ph.pt); | ||
211 | return 0; | ||
212 | } | ||
213 | |||
214 | /* | ||
215 | * Get response for readpage command. We search inode and page in its mapping | ||
216 | * and copy data into. If it was async request, then we queue page into shared | ||
217 | * data and wakeup listener, who will copy it to userspace. | ||
218 | * | ||
219 | * There is a work in progress of allowing to call copy_to_user() directly from | ||
220 | * async receiving kernel thread. | ||
221 | */ | ||
222 | static int pohmelfs_read_page_response(struct netfs_state *st) | ||
223 | { | ||
224 | struct pohmelfs_sb *psb = st->psb; | ||
225 | struct netfs_cmd *cmd = &st->cmd; | ||
226 | struct inode *inode; | ||
227 | struct page *page; | ||
228 | int err = 0; | ||
229 | |||
230 | if (cmd->size > PAGE_CACHE_SIZE) { | ||
231 | err = -EINVAL; | ||
232 | goto err_out_exit; | ||
233 | } | ||
234 | |||
235 | inode = ilookup(st->psb->sb, cmd->id); | ||
236 | if (!inode) { | ||
237 | printk("%s: failed to find inode: id: %llu.\n", __func__, cmd->id); | ||
238 | err = -ENOENT; | ||
239 | goto err_out_exit; | ||
240 | } | ||
241 | |||
242 | page = find_get_page(inode->i_mapping, cmd->start >> PAGE_CACHE_SHIFT); | ||
243 | if (!page || !PageLocked(page)) { | ||
244 | printk("%s: failed to find/lock page: page: %p, id: %llu, start: %llu, index: %llu.\n", | ||
245 | __func__, page, cmd->id, cmd->start, cmd->start >> PAGE_CACHE_SHIFT); | ||
246 | |||
247 | while (cmd->size) { | ||
248 | unsigned int sz = min(cmd->size, st->size); | ||
249 | |||
250 | err = pohmelfs_data_recv(st, st->data, sz); | ||
251 | if (err) | ||
252 | break; | ||
253 | |||
254 | cmd->size -= sz; | ||
255 | } | ||
256 | |||
257 | err = -ENODEV; | ||
258 | if (page) | ||
259 | goto err_out_page_put; | ||
260 | goto err_out_put; | ||
261 | } | ||
262 | |||
263 | if (cmd->size) { | ||
264 | void *addr; | ||
265 | |||
266 | addr = kmap(page); | ||
267 | err = pohmelfs_data_recv(st, addr, cmd->size); | ||
268 | kunmap(page); | ||
269 | |||
270 | if (err) | ||
271 | goto err_out_page_unlock; | ||
272 | } | ||
273 | |||
274 | dprintk("%s: page: %p, start: %llu, size: %u, locked: %d.\n", | ||
275 | __func__, page, cmd->start, cmd->size, PageLocked(page)); | ||
276 | |||
277 | SetPageChecked(page); | ||
278 | if ((psb->hash_string || psb->cipher_string) && psb->perform_crypto && cmd->size) { | ||
279 | err = pohmelfs_crypto_process_input_page(&st->eng, page, cmd->size, cmd->iv); | ||
280 | if (err < 0) | ||
281 | goto err_out_page_unlock; | ||
282 | } else { | ||
283 | SetPageUptodate(page); | ||
284 | unlock_page(page); | ||
285 | page_cache_release(page); | ||
286 | } | ||
287 | |||
288 | pohmelfs_put_inode(POHMELFS_I(inode)); | ||
289 | wake_up(&st->psb->wait); | ||
290 | |||
291 | return 0; | ||
292 | |||
293 | err_out_page_unlock: | ||
294 | SetPageError(page); | ||
295 | unlock_page(page); | ||
296 | err_out_page_put: | ||
297 | page_cache_release(page); | ||
298 | err_out_put: | ||
299 | pohmelfs_put_inode(POHMELFS_I(inode)); | ||
300 | err_out_exit: | ||
301 | wake_up(&st->psb->wait); | ||
302 | return err; | ||
303 | } | ||
304 | |||
305 | static int pohmelfs_check_name(struct pohmelfs_inode *parent, struct qstr *str, | ||
306 | struct netfs_inode_info *info) | ||
307 | { | ||
308 | struct inode *inode; | ||
309 | struct pohmelfs_name *n; | ||
310 | int err = 0; | ||
311 | u64 ino = 0; | ||
312 | |||
313 | mutex_lock(&parent->offset_lock); | ||
314 | n = pohmelfs_search_hash(parent, str->hash); | ||
315 | if (n) | ||
316 | ino = n->ino; | ||
317 | mutex_unlock(&parent->offset_lock); | ||
318 | |||
319 | if (!ino) | ||
320 | goto out; | ||
321 | |||
322 | inode = ilookup(parent->vfs_inode.i_sb, ino); | ||
323 | if (!inode) | ||
324 | goto out; | ||
325 | |||
326 | dprintk("%s: parent: %llu, inode: %llu.\n", __func__, parent->ino, ino); | ||
327 | |||
328 | pohmelfs_fill_inode(inode, info); | ||
329 | pohmelfs_put_inode(POHMELFS_I(inode)); | ||
330 | err = -EEXIST; | ||
331 | out: | ||
332 | return err; | ||
333 | } | ||
334 | |||
335 | /* | ||
336 | * Readdir response from server. If special field is set, we wakeup | ||
337 | * listener (readdir() call), which will copy data to userspace. | ||
338 | */ | ||
339 | static int pohmelfs_readdir_response(struct netfs_state *st) | ||
340 | { | ||
341 | struct inode *inode; | ||
342 | struct netfs_cmd *cmd = &st->cmd; | ||
343 | struct netfs_inode_info *info; | ||
344 | struct pohmelfs_inode *parent = NULL, *npi; | ||
345 | int err = 0, last = cmd->ext; | ||
346 | struct qstr str; | ||
347 | |||
348 | if (cmd->size > st->size) | ||
349 | return -EINVAL; | ||
350 | |||
351 | inode = ilookup(st->psb->sb, cmd->id); | ||
352 | if (!inode) { | ||
353 | printk("%s: failed to find inode: id: %llu.\n", __func__, cmd->id); | ||
354 | return -ENOENT; | ||
355 | } | ||
356 | parent = POHMELFS_I(inode); | ||
357 | |||
358 | if (!cmd->size && cmd->start) { | ||
359 | err = -cmd->start; | ||
360 | goto out; | ||
361 | } | ||
362 | |||
363 | if (cmd->size) { | ||
364 | char *name; | ||
365 | |||
366 | err = pohmelfs_data_recv_and_check(st, st->data, cmd->size); | ||
367 | if (err) | ||
368 | goto err_out_put; | ||
369 | |||
370 | info = (struct netfs_inode_info *)(st->data); | ||
371 | |||
372 | name = (char *)(info + 1); | ||
373 | str.len = cmd->size - sizeof(struct netfs_inode_info) - 1 - cmd->cpad; | ||
374 | name[str.len] = 0; | ||
375 | str.name = name; | ||
376 | str.hash = jhash(str.name, str.len, 0); | ||
377 | |||
378 | netfs_convert_inode_info(info); | ||
379 | |||
380 | if (parent) { | ||
381 | err = pohmelfs_check_name(parent, &str, info); | ||
382 | if (err) { | ||
383 | if (err == -EEXIST) | ||
384 | err = 0; | ||
385 | goto out; | ||
386 | } | ||
387 | } | ||
388 | |||
389 | info->ino = cmd->start; | ||
390 | if (!info->ino) | ||
391 | info->ino = pohmelfs_new_ino(st->psb); | ||
392 | |||
393 | dprintk("%s: parent: %llu, ino: %llu, name: '%s', hash: %x, len: %u, mode: %o.\n", | ||
394 | __func__, parent->ino, info->ino, str.name, str.hash, str.len, | ||
395 | info->mode); | ||
396 | |||
397 | npi = pohmelfs_new_inode(st->psb, parent, &str, info, 0); | ||
398 | if (IS_ERR(npi)) { | ||
399 | err = PTR_ERR(npi); | ||
400 | |||
401 | if (err != -EEXIST) | ||
402 | goto err_out_put; | ||
403 | } else { | ||
404 | struct dentry *dentry, *alias, *pd; | ||
405 | |||
406 | set_bit(NETFS_INODE_REMOTE_SYNCED, &npi->state); | ||
407 | clear_bit(NETFS_INODE_OWNED, &npi->state); | ||
408 | |||
409 | pd = d_find_alias(&parent->vfs_inode); | ||
410 | if (pd) { | ||
411 | str.hash = full_name_hash(str.name, str.len); | ||
412 | dentry = d_alloc(pd, &str); | ||
413 | if (dentry) { | ||
414 | alias = d_materialise_unique(dentry, &npi->vfs_inode); | ||
415 | if (alias) | ||
416 | dput(alias); | ||
417 | } | ||
418 | |||
419 | dput(dentry); | ||
420 | dput(pd); | ||
421 | } | ||
422 | } | ||
423 | } | ||
424 | out: | ||
425 | if (last) { | ||
426 | set_bit(NETFS_INODE_REMOTE_DIR_SYNCED, &parent->state); | ||
427 | set_bit(NETFS_INODE_REMOTE_SYNCED, &parent->state); | ||
428 | wake_up(&st->psb->wait); | ||
429 | } | ||
430 | pohmelfs_put_inode(parent); | ||
431 | |||
432 | return err; | ||
433 | |||
434 | err_out_put: | ||
435 | clear_bit(NETFS_INODE_REMOTE_DIR_SYNCED, &parent->state); | ||
436 | printk("%s: parent: %llu, ino: %llu, cmd_id: %llu.\n", __func__, parent->ino, cmd->start, cmd->id); | ||
437 | pohmelfs_put_inode(parent); | ||
438 | wake_up(&st->psb->wait); | ||
439 | return err; | ||
440 | } | ||
441 | |||
442 | /* | ||
443 | * Lookup command response. | ||
444 | * It searches for inode to be looked at (if it exists) and substitutes | ||
445 | * its inode information (size, permission, mode and so on), if inode does | ||
446 | * not exist, new one will be created and inserted into caches. | ||
447 | */ | ||
448 | static int pohmelfs_lookup_response(struct netfs_state *st) | ||
449 | { | ||
450 | struct inode *inode = NULL; | ||
451 | struct netfs_cmd *cmd = &st->cmd; | ||
452 | struct netfs_inode_info *info; | ||
453 | struct pohmelfs_inode *parent = NULL, *npi; | ||
454 | int err = -EINVAL; | ||
455 | char *name; | ||
456 | |||
457 | inode = ilookup(st->psb->sb, cmd->id); | ||
458 | if (!inode) { | ||
459 | printk("%s: lookup response: id: %llu, start: %llu, size: %u.\n", | ||
460 | __func__, cmd->id, cmd->start, cmd->size); | ||
461 | err = -ENOENT; | ||
462 | goto err_out_exit; | ||
463 | } | ||
464 | parent = POHMELFS_I(inode); | ||
465 | |||
466 | if (!cmd->size) { | ||
467 | err = -cmd->start; | ||
468 | goto err_out_put; | ||
469 | } | ||
470 | |||
471 | if (cmd->size < sizeof(struct netfs_inode_info)) { | ||
472 | printk("%s: broken lookup response: id: %llu, start: %llu, size: %u.\n", | ||
473 | __func__, cmd->id, cmd->start, cmd->size); | ||
474 | err = -EINVAL; | ||
475 | goto err_out_put; | ||
476 | } | ||
477 | |||
478 | err = pohmelfs_data_recv_and_check(st, st->data, cmd->size); | ||
479 | if (err) | ||
480 | goto err_out_put; | ||
481 | |||
482 | info = (struct netfs_inode_info *)(st->data); | ||
483 | name = (char *)(info + 1); | ||
484 | |||
485 | netfs_convert_inode_info(info); | ||
486 | |||
487 | info->ino = cmd->start; | ||
488 | if (!info->ino) | ||
489 | info->ino = pohmelfs_new_ino(st->psb); | ||
490 | |||
491 | dprintk("%s: parent: %llu, ino: %llu, name: '%s', start: %llu.\n", | ||
492 | __func__, parent->ino, info->ino, name, cmd->start); | ||
493 | |||
494 | if (cmd->start) | ||
495 | npi = pohmelfs_new_inode(st->psb, parent, NULL, info, 0); | ||
496 | else { | ||
497 | struct qstr str; | ||
498 | |||
499 | str.name = name; | ||
500 | str.len = cmd->size - sizeof(struct netfs_inode_info) - 1 - cmd->cpad; | ||
501 | str.hash = jhash(name, str.len, 0); | ||
502 | |||
503 | npi = pohmelfs_new_inode(st->psb, parent, &str, info, 0); | ||
504 | } | ||
505 | if (IS_ERR(npi)) { | ||
506 | err = PTR_ERR(npi); | ||
507 | |||
508 | if (err != -EEXIST) | ||
509 | goto err_out_put; | ||
510 | } else { | ||
511 | set_bit(NETFS_INODE_REMOTE_SYNCED, &npi->state); | ||
512 | clear_bit(NETFS_INODE_OWNED, &npi->state); | ||
513 | } | ||
514 | |||
515 | clear_bit(NETFS_COMMAND_PENDING, &parent->state); | ||
516 | pohmelfs_put_inode(parent); | ||
517 | |||
518 | wake_up(&st->psb->wait); | ||
519 | |||
520 | return 0; | ||
521 | |||
522 | err_out_put: | ||
523 | pohmelfs_put_inode(parent); | ||
524 | err_out_exit: | ||
525 | clear_bit(NETFS_COMMAND_PENDING, &parent->state); | ||
526 | wake_up(&st->psb->wait); | ||
527 | printk("%s: inode: %p, id: %llu, start: %llu, size: %u, err: %d.\n", | ||
528 | __func__, inode, cmd->id, cmd->start, cmd->size, err); | ||
529 | return err; | ||
530 | } | ||
531 | |||
532 | /* | ||
533 | * Create response, just marks local inode as 'created', so that writeback | ||
534 | * for any of its children (or own) would not try to sync it again. | ||
535 | */ | ||
536 | static int pohmelfs_create_response(struct netfs_state *st) | ||
537 | { | ||
538 | struct inode *inode; | ||
539 | struct netfs_cmd *cmd = &st->cmd; | ||
540 | struct pohmelfs_inode *pi; | ||
541 | |||
542 | inode = ilookup(st->psb->sb, cmd->id); | ||
543 | if (!inode) { | ||
544 | printk("%s: failed to find inode: id: %llu, start: %llu.\n", | ||
545 | __func__, cmd->id, cmd->start); | ||
546 | goto err_out_exit; | ||
547 | } | ||
548 | |||
549 | pi = POHMELFS_I(inode); | ||
550 | |||
551 | /* | ||
552 | * To lock or not to lock? | ||
553 | * We actually do not care if it races... | ||
554 | */ | ||
555 | if (cmd->start) | ||
556 | make_bad_inode(inode); | ||
557 | set_bit(NETFS_INODE_REMOTE_SYNCED, &pi->state); | ||
558 | |||
559 | pohmelfs_put_inode(pi); | ||
560 | |||
561 | wake_up(&st->psb->wait); | ||
562 | return 0; | ||
563 | |||
564 | err_out_exit: | ||
565 | wake_up(&st->psb->wait); | ||
566 | return -ENOENT; | ||
567 | } | ||
568 | |||
569 | /* | ||
570 | * Object remove response. Just says that remove request has been received. | ||
571 | * Used in cache coherency protocol. | ||
572 | */ | ||
573 | static int pohmelfs_remove_response(struct netfs_state *st) | ||
574 | { | ||
575 | struct netfs_cmd *cmd = &st->cmd; | ||
576 | int err; | ||
577 | |||
578 | err = pohmelfs_data_recv_and_check(st, st->data, cmd->size); | ||
579 | if (err) | ||
580 | return err; | ||
581 | |||
582 | dprintk("%s: parent: %llu, path: '%s'.\n", __func__, cmd->id, (char *)st->data); | ||
583 | |||
584 | return 0; | ||
585 | } | ||
586 | |||
587 | /* | ||
588 | * Transaction reply processing. | ||
589 | * | ||
590 | * Find transaction based on its generation number, bump its reference counter, | ||
591 | * so that none could free it under us, drop from the trees and lists and | ||
592 | * drop reference counter. When it hits zero (when all destinations replied | ||
593 | * and all timeout handled by async scanning code), completion will be called | ||
594 | * and transaction will be freed. | ||
595 | */ | ||
596 | static int pohmelfs_transaction_response(struct netfs_state *st) | ||
597 | { | ||
598 | struct netfs_trans_dst *dst; | ||
599 | struct netfs_trans *t = NULL; | ||
600 | struct netfs_cmd *cmd = &st->cmd; | ||
601 | short err = (signed)cmd->ext; | ||
602 | |||
603 | mutex_lock(&st->trans_lock); | ||
604 | dst = netfs_trans_search(st, cmd->start); | ||
605 | if (dst) { | ||
606 | netfs_trans_remove_nolock(dst, st); | ||
607 | t = dst->trans; | ||
608 | } | ||
609 | mutex_unlock(&st->trans_lock); | ||
610 | |||
611 | if (!t) { | ||
612 | printk("%s: failed to find transaction: start: %llu: id: %llu, size: %u, ext: %u.\n", | ||
613 | __func__, cmd->start, cmd->id, cmd->size, cmd->ext); | ||
614 | err = -EINVAL; | ||
615 | goto out; | ||
616 | } | ||
617 | |||
618 | t->result = err; | ||
619 | netfs_trans_drop_dst_nostate(dst); | ||
620 | |||
621 | out: | ||
622 | wake_up(&st->psb->wait); | ||
623 | return err; | ||
624 | } | ||
625 | |||
626 | /* | ||
627 | * Inode metadata cache coherency message. | ||
628 | */ | ||
629 | static int pohmelfs_page_cache_response(struct netfs_state *st) | ||
630 | { | ||
631 | struct netfs_cmd *cmd = &st->cmd; | ||
632 | struct inode *inode; | ||
633 | |||
634 | dprintk("%s: st: %p, id: %llu, start: %llu, size: %u.\n", __func__, st, cmd->id, cmd->start, cmd->size); | ||
635 | |||
636 | inode = ilookup(st->psb->sb, cmd->id); | ||
637 | if (!inode) { | ||
638 | printk("%s: failed to find inode: id: %llu.\n", __func__, cmd->id); | ||
639 | return -ENOENT; | ||
640 | } | ||
641 | |||
642 | set_bit(NETFS_INODE_NEED_FLUSH, &POHMELFS_I(inode)->state); | ||
643 | pohmelfs_put_inode(POHMELFS_I(inode)); | ||
644 | |||
645 | return 0; | ||
646 | } | ||
647 | |||
648 | /* | ||
649 | * Root capabilities response: export statistics | ||
650 | * like used and available size, number of files and dirs, | ||
651 | * permissions. | ||
652 | */ | ||
653 | static int pohmelfs_root_cap_response(struct netfs_state *st) | ||
654 | { | ||
655 | struct netfs_cmd *cmd = &st->cmd; | ||
656 | struct netfs_root_capabilities *cap; | ||
657 | struct pohmelfs_sb *psb = st->psb; | ||
658 | |||
659 | if (cmd->size != sizeof(struct netfs_root_capabilities)) { | ||
660 | psb->flags = EPROTO; | ||
661 | wake_up(&psb->wait); | ||
662 | return -EPROTO; | ||
663 | } | ||
664 | |||
665 | cap = st->data; | ||
666 | |||
667 | netfs_convert_root_capabilities(cap); | ||
668 | |||
669 | if (psb->total_size < cap->used + cap->avail) | ||
670 | psb->total_size = cap->used + cap->avail; | ||
671 | if (cap->avail) | ||
672 | psb->avail_size = cap->avail; | ||
673 | psb->state_flags = cap->flags; | ||
674 | |||
675 | if (psb->state_flags & POHMELFS_FLAGS_RO) { | ||
676 | psb->sb->s_flags |= MS_RDONLY; | ||
677 | printk(KERN_INFO "Mounting POHMELFS (%d) read-only.\n", psb->idx); | ||
678 | } | ||
679 | |||
680 | if (psb->state_flags & POHMELFS_FLAGS_XATTR) | ||
681 | printk(KERN_INFO "Mounting POHMELFS (%d) " | ||
682 | "with extended attributes support.\n", psb->idx); | ||
683 | |||
684 | if (atomic_long_read(&psb->total_inodes) <= 1) | ||
685 | atomic_long_set(&psb->total_inodes, cap->nr_files); | ||
686 | |||
687 | dprintk("%s: total: %llu, avail: %llu, flags: %llx, inodes: %llu.\n", | ||
688 | __func__, psb->total_size, psb->avail_size, psb->state_flags, cap->nr_files); | ||
689 | |||
690 | psb->flags = 0; | ||
691 | wake_up(&psb->wait); | ||
692 | return 0; | ||
693 | } | ||
694 | |||
695 | /* | ||
696 | * Crypto capabilities of the server, where it says that | ||
697 | * it supports or does not requested hash/cipher algorithms. | ||
698 | */ | ||
699 | static int pohmelfs_crypto_cap_response(struct netfs_state *st) | ||
700 | { | ||
701 | struct netfs_cmd *cmd = &st->cmd; | ||
702 | struct netfs_crypto_capabilities *cap; | ||
703 | struct pohmelfs_sb *psb = st->psb; | ||
704 | int err = 0; | ||
705 | |||
706 | if (cmd->size != sizeof(struct netfs_crypto_capabilities)) { | ||
707 | psb->flags = EPROTO; | ||
708 | wake_up(&psb->wait); | ||
709 | return -EPROTO; | ||
710 | } | ||
711 | |||
712 | cap = st->data; | ||
713 | |||
714 | dprintk("%s: cipher '%s': %s, hash: '%s': %s.\n", | ||
715 | __func__, | ||
716 | psb->cipher_string, (cap->cipher_strlen) ? "SUPPORTED" : "NOT SUPPORTED", | ||
717 | psb->hash_string, (cap->hash_strlen) ? "SUPPORTED" : "NOT SUPPORTED"); | ||
718 | |||
719 | if (!cap->hash_strlen) { | ||
720 | if (psb->hash_strlen && psb->crypto_fail_unsupported) | ||
721 | err = -ENOTSUPP; | ||
722 | psb->hash_strlen = 0; | ||
723 | kfree(psb->hash_string); | ||
724 | psb->hash_string = NULL; | ||
725 | } | ||
726 | |||
727 | if (!cap->cipher_strlen) { | ||
728 | if (psb->cipher_strlen && psb->crypto_fail_unsupported) | ||
729 | err = -ENOTSUPP; | ||
730 | psb->cipher_strlen = 0; | ||
731 | kfree(psb->cipher_string); | ||
732 | psb->cipher_string = NULL; | ||
733 | } | ||
734 | |||
735 | return err; | ||
736 | } | ||
737 | |||
738 | /* | ||
739 | * Capabilities handshake response. | ||
740 | */ | ||
741 | static int pohmelfs_capabilities_response(struct netfs_state *st) | ||
742 | { | ||
743 | struct netfs_cmd *cmd = &st->cmd; | ||
744 | int err = 0; | ||
745 | |||
746 | err = pohmelfs_data_recv(st, st->data, cmd->size); | ||
747 | if (err) | ||
748 | return err; | ||
749 | |||
750 | switch (cmd->id) { | ||
751 | case POHMELFS_CRYPTO_CAPABILITIES: | ||
752 | return pohmelfs_crypto_cap_response(st); | ||
753 | case POHMELFS_ROOT_CAPABILITIES: | ||
754 | return pohmelfs_root_cap_response(st); | ||
755 | default: | ||
756 | break; | ||
757 | } | ||
758 | return -EINVAL; | ||
759 | } | ||
760 | |||
761 | /* | ||
762 | * Receiving extended attribute. | ||
763 | * Does not work properly if received size is more than requested one, | ||
764 | * it should not happen with current request/reply model though. | ||
765 | */ | ||
766 | static int pohmelfs_getxattr_response(struct netfs_state *st) | ||
767 | { | ||
768 | struct pohmelfs_sb *psb = st->psb; | ||
769 | struct netfs_cmd *cmd = &st->cmd; | ||
770 | struct pohmelfs_mcache *m; | ||
771 | short error = (signed short)cmd->ext, err; | ||
772 | unsigned int sz, total_size; | ||
773 | |||
774 | m = pohmelfs_mcache_search(psb, cmd->id); | ||
775 | |||
776 | dprintk("%s: id: %llu, gen: %llu, err: %d.\n", | ||
777 | __func__, cmd->id, (m) ? m->gen : 0, error); | ||
778 | |||
779 | if (!m) { | ||
780 | printk("%s: failed to find getxattr cache entry: id: %llu.\n", __func__, cmd->id); | ||
781 | return -ENOENT; | ||
782 | } | ||
783 | |||
784 | if (cmd->size) { | ||
785 | sz = min_t(unsigned int, cmd->size, m->size); | ||
786 | err = pohmelfs_data_recv_and_check(st, m->data, sz); | ||
787 | if (err) { | ||
788 | error = err; | ||
789 | goto out; | ||
790 | } | ||
791 | |||
792 | m->size = sz; | ||
793 | total_size = cmd->size - sz; | ||
794 | |||
795 | while (total_size) { | ||
796 | sz = min(total_size, st->size); | ||
797 | |||
798 | err = pohmelfs_data_recv_and_check(st, st->data, sz); | ||
799 | if (err) { | ||
800 | error = err; | ||
801 | break; | ||
802 | } | ||
803 | |||
804 | total_size -= sz; | ||
805 | } | ||
806 | } | ||
807 | |||
808 | out: | ||
809 | m->err = error; | ||
810 | complete(&m->complete); | ||
811 | pohmelfs_mcache_put(psb, m); | ||
812 | |||
813 | return error; | ||
814 | } | ||
815 | |||
816 | int pohmelfs_data_lock_response(struct netfs_state *st) | ||
817 | { | ||
818 | struct pohmelfs_sb *psb = st->psb; | ||
819 | struct netfs_cmd *cmd = &st->cmd; | ||
820 | struct pohmelfs_mcache *m; | ||
821 | short err = (signed short)cmd->ext; | ||
822 | u64 id = cmd->id; | ||
823 | |||
824 | m = pohmelfs_mcache_search(psb, id); | ||
825 | |||
826 | dprintk("%s: id: %llu, gen: %llu, err: %d.\n", | ||
827 | __func__, cmd->id, (m) ? m->gen : 0, err); | ||
828 | |||
829 | if (!m) { | ||
830 | pohmelfs_data_recv(st, st->data, cmd->size); | ||
831 | printk("%s: failed to find data lock response: id: %llu.\n", __func__, cmd->id); | ||
832 | return -ENOENT; | ||
833 | } | ||
834 | |||
835 | if (cmd->size) | ||
836 | err = pohmelfs_data_recv_and_check(st, &m->info, cmd->size); | ||
837 | |||
838 | m->err = err; | ||
839 | complete(&m->complete); | ||
840 | pohmelfs_mcache_put(psb, m); | ||
841 | |||
842 | return err; | ||
843 | } | ||
844 | |||
845 | static void __inline__ netfs_state_reset(struct netfs_state *st) | ||
846 | { | ||
847 | netfs_state_lock_send(st); | ||
848 | netfs_state_exit(st); | ||
849 | netfs_state_init(st); | ||
850 | netfs_state_unlock_send(st); | ||
851 | } | ||
852 | |||
853 | /* | ||
854 | * Main receiving function, called from dedicated kernel thread. | ||
855 | */ | ||
856 | static int pohmelfs_recv(void *data) | ||
857 | { | ||
858 | int err = -EINTR; | ||
859 | struct netfs_state *st = data; | ||
860 | struct netfs_cmd *cmd = &st->cmd; | ||
861 | |||
862 | while (!kthread_should_stop()) { | ||
863 | /* | ||
864 | * If socket will be reset after this statement, then | ||
865 | * pohmelfs_data_recv() will just fail and loop will | ||
866 | * start again, so it can be done without any locks. | ||
867 | * | ||
868 | * st->read_socket is needed to prevents state machine | ||
869 | * breaking between this data reading and subsequent one | ||
870 | * in protocol specific functions during connection reset. | ||
871 | * In case of reset we have to read next command and do | ||
872 | * not expect data for old command to magically appear in | ||
873 | * new connection. | ||
874 | */ | ||
875 | st->read_socket = st->socket; | ||
876 | err = pohmelfs_data_recv(st, cmd, sizeof(struct netfs_cmd)); | ||
877 | if (err) { | ||
878 | msleep(1000); | ||
879 | continue; | ||
880 | } | ||
881 | |||
882 | netfs_convert_cmd(cmd); | ||
883 | |||
884 | dprintk("%s: cmd: %u, id: %llu, start: %llu, size: %u, " | ||
885 | "ext: %u, csize: %u, cpad: %u.\n", | ||
886 | __func__, cmd->cmd, cmd->id, cmd->start, | ||
887 | cmd->size, cmd->ext, cmd->csize, cmd->cpad); | ||
888 | |||
889 | if (cmd->csize) { | ||
890 | struct pohmelfs_crypto_engine *e = &st->eng; | ||
891 | |||
892 | if (unlikely(cmd->csize > e->size/2)) { | ||
893 | netfs_state_reset(st); | ||
894 | continue; | ||
895 | } | ||
896 | |||
897 | if (e->hash && unlikely(cmd->csize != st->psb->crypto_attached_size)) { | ||
898 | dprintk("%s: cmd: cmd: %u, id: %llu, start: %llu, size: %u, " | ||
899 | "csize: %u != digest size %u.\n", | ||
900 | __func__, cmd->cmd, cmd->id, cmd->start, cmd->size, | ||
901 | cmd->csize, st->psb->crypto_attached_size); | ||
902 | netfs_state_reset(st); | ||
903 | continue; | ||
904 | } | ||
905 | |||
906 | err = pohmelfs_data_recv(st, e->data, cmd->csize); | ||
907 | if (err) { | ||
908 | netfs_state_reset(st); | ||
909 | continue; | ||
910 | } | ||
911 | |||
912 | #ifdef CONFIG_POHMELFS_DEBUG | ||
913 | { | ||
914 | unsigned int i; | ||
915 | unsigned char *hash = e->data; | ||
916 | |||
917 | dprintk("%s: received hash: ", __func__); | ||
918 | for (i = 0; i < cmd->csize; ++i) | ||
919 | printk("%02x ", hash[i]); | ||
920 | |||
921 | printk("\n"); | ||
922 | } | ||
923 | #endif | ||
924 | cmd->size -= cmd->csize; | ||
925 | } | ||
926 | |||
927 | /* | ||
928 | * This should catch protocol breakage and random garbage instead of commands. | ||
929 | */ | ||
930 | if (unlikely((cmd->size > st->size) && (cmd->cmd != NETFS_XATTR_GET))) { | ||
931 | netfs_state_reset(st); | ||
932 | continue; | ||
933 | } | ||
934 | |||
935 | switch (cmd->cmd) { | ||
936 | case NETFS_READ_PAGE: | ||
937 | err = pohmelfs_read_page_response(st); | ||
938 | break; | ||
939 | case NETFS_READDIR: | ||
940 | err = pohmelfs_readdir_response(st); | ||
941 | break; | ||
942 | case NETFS_LOOKUP: | ||
943 | err = pohmelfs_lookup_response(st); | ||
944 | break; | ||
945 | case NETFS_CREATE: | ||
946 | err = pohmelfs_create_response(st); | ||
947 | break; | ||
948 | case NETFS_REMOVE: | ||
949 | err = pohmelfs_remove_response(st); | ||
950 | break; | ||
951 | case NETFS_TRANS: | ||
952 | err = pohmelfs_transaction_response(st); | ||
953 | break; | ||
954 | case NETFS_PAGE_CACHE: | ||
955 | err = pohmelfs_page_cache_response(st); | ||
956 | break; | ||
957 | case NETFS_CAPABILITIES: | ||
958 | err = pohmelfs_capabilities_response(st); | ||
959 | break; | ||
960 | case NETFS_LOCK: | ||
961 | err = pohmelfs_data_lock_response(st); | ||
962 | break; | ||
963 | case NETFS_XATTR_GET: | ||
964 | err = pohmelfs_getxattr_response(st); | ||
965 | break; | ||
966 | default: | ||
967 | printk("%s: wrong cmd: %u, id: %llu, start: %llu, size: %u, ext: %u.\n", | ||
968 | __func__, cmd->cmd, cmd->id, cmd->start, cmd->size, cmd->ext); | ||
969 | netfs_state_reset(st); | ||
970 | break; | ||
971 | } | ||
972 | } | ||
973 | |||
974 | while (!kthread_should_stop()) | ||
975 | schedule_timeout_uninterruptible(msecs_to_jiffies(10)); | ||
976 | |||
977 | return err; | ||
978 | } | ||
979 | |||
980 | int netfs_state_init(struct netfs_state *st) | ||
981 | { | ||
982 | int err; | ||
983 | struct pohmelfs_ctl *ctl = &st->ctl; | ||
984 | |||
985 | err = sock_create(ctl->addr.sa_family, ctl->type, ctl->proto, &st->socket); | ||
986 | if (err) { | ||
987 | printk("%s: failed to create a socket: family: %d, type: %d, proto: %d, err: %d.\n", | ||
988 | __func__, ctl->addr.sa_family, ctl->type, ctl->proto, err); | ||
989 | goto err_out_exit; | ||
990 | } | ||
991 | |||
992 | st->socket->sk->sk_allocation = GFP_NOIO; | ||
993 | st->socket->sk->sk_sndtimeo = st->socket->sk->sk_rcvtimeo = msecs_to_jiffies(60000); | ||
994 | |||
995 | err = kernel_connect(st->socket, (struct sockaddr *)&ctl->addr, ctl->addrlen, 0); | ||
996 | if (err) { | ||
997 | printk("%s: failed to connect to server: idx: %u, err: %d.\n", | ||
998 | __func__, st->psb->idx, err); | ||
999 | goto err_out_release; | ||
1000 | } | ||
1001 | st->socket->sk->sk_sndtimeo = st->socket->sk->sk_rcvtimeo = msecs_to_jiffies(60000); | ||
1002 | |||
1003 | err = netfs_poll_init(st); | ||
1004 | if (err) | ||
1005 | goto err_out_release; | ||
1006 | |||
1007 | if (st->socket->ops->family == AF_INET) { | ||
1008 | struct sockaddr_in *sin = (struct sockaddr_in *)&ctl->addr; | ||
1009 | printk(KERN_INFO "%s: (re)connected to peer %pi4:%d.\n", __func__, | ||
1010 | &sin->sin_addr.s_addr, ntohs(sin->sin_port)); | ||
1011 | } else if (st->socket->ops->family == AF_INET6) { | ||
1012 | struct sockaddr_in6 *sin = (struct sockaddr_in6 *)&ctl->addr; | ||
1013 | printk(KERN_INFO "%s: (re)connected to peer %pi6:%d", __func__, | ||
1014 | &sin->sin6_addr, ntohs(sin->sin6_port)); | ||
1015 | } | ||
1016 | |||
1017 | return 0; | ||
1018 | |||
1019 | err_out_release: | ||
1020 | sock_release(st->socket); | ||
1021 | err_out_exit: | ||
1022 | st->socket = NULL; | ||
1023 | return err; | ||
1024 | } | ||
1025 | |||
1026 | void netfs_state_exit(struct netfs_state *st) | ||
1027 | { | ||
1028 | if (st->socket) { | ||
1029 | netfs_poll_exit(st); | ||
1030 | st->socket->ops->shutdown(st->socket, 2); | ||
1031 | |||
1032 | if (st->socket->ops->family == AF_INET) { | ||
1033 | struct sockaddr_in *sin = (struct sockaddr_in *)&st->ctl.addr; | ||
1034 | printk(KERN_INFO "%s: disconnected from peer %pi4:%d.\n", __func__, | ||
1035 | &sin->sin_addr.s_addr, ntohs(sin->sin_port)); | ||
1036 | } else if (st->socket->ops->family == AF_INET6) { | ||
1037 | struct sockaddr_in6 *sin = (struct sockaddr_in6 *)&st->ctl.addr; | ||
1038 | printk(KERN_INFO "%s: disconnected from peer %pi6:%d", __func__, | ||
1039 | &sin->sin6_addr, ntohs(sin->sin6_port)); | ||
1040 | } | ||
1041 | |||
1042 | sock_release(st->socket); | ||
1043 | st->socket = NULL; | ||
1044 | st->read_socket = NULL; | ||
1045 | st->need_reset = 0; | ||
1046 | } | ||
1047 | } | ||
1048 | |||
1049 | int pohmelfs_state_init_one(struct pohmelfs_sb *psb, struct pohmelfs_config *conf) | ||
1050 | { | ||
1051 | struct netfs_state *st = &conf->state; | ||
1052 | int err = -ENOMEM; | ||
1053 | |||
1054 | mutex_init(&st->__state_lock); | ||
1055 | mutex_init(&st->__state_send_lock); | ||
1056 | init_waitqueue_head(&st->thread_wait); | ||
1057 | |||
1058 | st->psb = psb; | ||
1059 | st->trans_root = RB_ROOT; | ||
1060 | mutex_init(&st->trans_lock); | ||
1061 | |||
1062 | st->size = psb->trans_data_size; | ||
1063 | st->data = kmalloc(st->size, GFP_KERNEL); | ||
1064 | if (!st->data) | ||
1065 | goto err_out_exit; | ||
1066 | |||
1067 | if (psb->perform_crypto) { | ||
1068 | err = pohmelfs_crypto_engine_init(&st->eng, psb); | ||
1069 | if (err) | ||
1070 | goto err_out_free_data; | ||
1071 | } | ||
1072 | |||
1073 | err = netfs_state_init(st); | ||
1074 | if (err) | ||
1075 | goto err_out_free_engine; | ||
1076 | |||
1077 | st->thread = kthread_run(pohmelfs_recv, st, "pohmelfs/%u", psb->idx); | ||
1078 | if (IS_ERR(st->thread)) { | ||
1079 | err = PTR_ERR(st->thread); | ||
1080 | goto err_out_netfs_exit; | ||
1081 | } | ||
1082 | |||
1083 | if (!psb->active_state) | ||
1084 | psb->active_state = conf; | ||
1085 | |||
1086 | dprintk("%s: conf: %p, st: %p, socket: %p.\n", | ||
1087 | __func__, conf, st, st->socket); | ||
1088 | return 0; | ||
1089 | |||
1090 | err_out_netfs_exit: | ||
1091 | netfs_state_exit(st); | ||
1092 | err_out_free_engine: | ||
1093 | pohmelfs_crypto_engine_exit(&st->eng); | ||
1094 | err_out_free_data: | ||
1095 | kfree(st->data); | ||
1096 | err_out_exit: | ||
1097 | return err; | ||
1098 | |||
1099 | } | ||
1100 | |||
1101 | void pohmelfs_state_flush_transactions(struct netfs_state *st) | ||
1102 | { | ||
1103 | struct rb_node *rb_node; | ||
1104 | struct netfs_trans_dst *dst; | ||
1105 | |||
1106 | mutex_lock(&st->trans_lock); | ||
1107 | for (rb_node = rb_first(&st->trans_root); rb_node; ) { | ||
1108 | dst = rb_entry(rb_node, struct netfs_trans_dst, state_entry); | ||
1109 | rb_node = rb_next(rb_node); | ||
1110 | |||
1111 | dst->trans->result = -EINVAL; | ||
1112 | netfs_trans_remove_nolock(dst, st); | ||
1113 | netfs_trans_drop_dst_nostate(dst); | ||
1114 | } | ||
1115 | mutex_unlock(&st->trans_lock); | ||
1116 | } | ||
1117 | |||
1118 | static void pohmelfs_state_exit_one(struct pohmelfs_config *c) | ||
1119 | { | ||
1120 | struct netfs_state *st = &c->state; | ||
1121 | |||
1122 | dprintk("%s: exiting, st: %p.\n", __func__, st); | ||
1123 | if (st->thread) { | ||
1124 | kthread_stop(st->thread); | ||
1125 | st->thread = NULL; | ||
1126 | } | ||
1127 | |||
1128 | netfs_state_lock_send(st); | ||
1129 | netfs_state_exit(st); | ||
1130 | netfs_state_unlock_send(st); | ||
1131 | |||
1132 | pohmelfs_state_flush_transactions(st); | ||
1133 | |||
1134 | pohmelfs_crypto_engine_exit(&st->eng); | ||
1135 | kfree(st->data); | ||
1136 | |||
1137 | kfree(c); | ||
1138 | } | ||
1139 | |||
1140 | /* | ||
1141 | * Initialize network stack. It searches for given ID in global | ||
1142 | * configuration table, this contains information of the remote server | ||
1143 | * (address (any supported by socket interface) and port, protocol and so on). | ||
1144 | */ | ||
1145 | int pohmelfs_state_init(struct pohmelfs_sb *psb) | ||
1146 | { | ||
1147 | int err = -ENOMEM; | ||
1148 | |||
1149 | err = pohmelfs_copy_config(psb); | ||
1150 | if (err) { | ||
1151 | pohmelfs_state_exit(psb); | ||
1152 | return err; | ||
1153 | } | ||
1154 | |||
1155 | return 0; | ||
1156 | } | ||
1157 | |||
1158 | void pohmelfs_state_exit(struct pohmelfs_sb *psb) | ||
1159 | { | ||
1160 | struct pohmelfs_config *c, *tmp; | ||
1161 | |||
1162 | list_for_each_entry_safe(c, tmp, &psb->state_list, config_entry) { | ||
1163 | list_del(&c->config_entry); | ||
1164 | pohmelfs_state_exit_one(c); | ||
1165 | } | ||
1166 | } | ||
1167 | |||
1168 | void pohmelfs_switch_active(struct pohmelfs_sb *psb) | ||
1169 | { | ||
1170 | struct pohmelfs_config *c = psb->active_state; | ||
1171 | |||
1172 | if (!list_empty(&psb->state_list)) { | ||
1173 | if (c->config_entry.next != &psb->state_list) { | ||
1174 | psb->active_state = list_entry(c->config_entry.next, | ||
1175 | struct pohmelfs_config, config_entry); | ||
1176 | } else { | ||
1177 | psb->active_state = list_entry(psb->state_list.next, | ||
1178 | struct pohmelfs_config, config_entry); | ||
1179 | } | ||
1180 | |||
1181 | dprintk("%s: empty: %d, active %p -> %p.\n", | ||
1182 | __func__, list_empty(&psb->state_list), c, | ||
1183 | psb->active_state); | ||
1184 | } else | ||
1185 | psb->active_state = NULL; | ||
1186 | } | ||
1187 | |||
1188 | void pohmelfs_check_states(struct pohmelfs_sb *psb) | ||
1189 | { | ||
1190 | struct pohmelfs_config *c, *tmp; | ||
1191 | LIST_HEAD(delete_list); | ||
1192 | |||
1193 | mutex_lock(&psb->state_lock); | ||
1194 | list_for_each_entry_safe(c, tmp, &psb->state_list, config_entry) { | ||
1195 | if (pohmelfs_config_check(c, psb->idx)) { | ||
1196 | |||
1197 | if (psb->active_state == c) | ||
1198 | pohmelfs_switch_active(psb); | ||
1199 | list_move(&c->config_entry, &delete_list); | ||
1200 | } | ||
1201 | } | ||
1202 | pohmelfs_copy_config(psb); | ||
1203 | mutex_unlock(&psb->state_lock); | ||
1204 | |||
1205 | list_for_each_entry_safe(c, tmp, &delete_list, config_entry) { | ||
1206 | list_del(&c->config_entry); | ||
1207 | pohmelfs_state_exit_one(c); | ||
1208 | } | ||
1209 | } | ||