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[linux-2.6/verdex.git] / fs / afs / cmservice.c
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1 /* cmservice.c: AFS Cache Manager Service
3 * Copyright (C) 2002 Red Hat, Inc. All Rights Reserved.
4 * Written by David Howells (dhowells@redhat.com)
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.
12 #include <linux/module.h>
13 #include <linux/init.h>
14 #include <linux/sched.h>
15 #include <linux/completion.h>
16 #include "server.h"
17 #include "cell.h"
18 #include "transport.h"
19 #include <rxrpc/rxrpc.h>
20 #include <rxrpc/transport.h>
21 #include <rxrpc/connection.h>
22 #include <rxrpc/call.h>
23 #include "cmservice.h"
24 #include "internal.h"
26 static unsigned afscm_usage; /* AFS cache manager usage count */
27 static struct rw_semaphore afscm_sem; /* AFS cache manager start/stop semaphore */
29 static int afscm_new_call(struct rxrpc_call *call);
30 static void afscm_attention(struct rxrpc_call *call);
31 static void afscm_error(struct rxrpc_call *call);
32 static void afscm_aemap(struct rxrpc_call *call);
34 static void _SRXAFSCM_CallBack(struct rxrpc_call *call);
35 static void _SRXAFSCM_InitCallBackState(struct rxrpc_call *call);
36 static void _SRXAFSCM_Probe(struct rxrpc_call *call);
38 typedef void (*_SRXAFSCM_xxxx_t)(struct rxrpc_call *call);
40 static const struct rxrpc_operation AFSCM_ops[] = {
42 .id = 204,
43 .asize = RXRPC_APP_MARK_EOF,
44 .name = "CallBack",
45 .user = _SRXAFSCM_CallBack,
48 .id = 205,
49 .asize = RXRPC_APP_MARK_EOF,
50 .name = "InitCallBackState",
51 .user = _SRXAFSCM_InitCallBackState,
54 .id = 206,
55 .asize = RXRPC_APP_MARK_EOF,
56 .name = "Probe",
57 .user = _SRXAFSCM_Probe,
59 #if 0
61 .id = 207,
62 .asize = RXRPC_APP_MARK_EOF,
63 .name = "GetLock",
64 .user = _SRXAFSCM_GetLock,
67 .id = 208,
68 .asize = RXRPC_APP_MARK_EOF,
69 .name = "GetCE",
70 .user = _SRXAFSCM_GetCE,
73 .id = 209,
74 .asize = RXRPC_APP_MARK_EOF,
75 .name = "GetXStatsVersion",
76 .user = _SRXAFSCM_GetXStatsVersion,
79 .id = 210,
80 .asize = RXRPC_APP_MARK_EOF,
81 .name = "GetXStats",
82 .user = _SRXAFSCM_GetXStats,
84 #endif
87 static struct rxrpc_service AFSCM_service = {
88 .name = "AFS/CM",
89 .owner = THIS_MODULE,
90 .link = LIST_HEAD_INIT(AFSCM_service.link),
91 .new_call = afscm_new_call,
92 .service_id = 1,
93 .attn_func = afscm_attention,
94 .error_func = afscm_error,
95 .aemap_func = afscm_aemap,
96 .ops_begin = &AFSCM_ops[0],
97 .ops_end = &AFSCM_ops[sizeof(AFSCM_ops) / sizeof(AFSCM_ops[0])],
100 static DECLARE_COMPLETION(kafscmd_alive);
101 static DECLARE_COMPLETION(kafscmd_dead);
102 static DECLARE_WAIT_QUEUE_HEAD(kafscmd_sleepq);
103 static LIST_HEAD(kafscmd_attention_list);
104 static LIST_HEAD(afscm_calls);
105 static DEFINE_SPINLOCK(afscm_calls_lock);
106 static DEFINE_SPINLOCK(kafscmd_attention_lock);
107 static int kafscmd_die;
109 /*****************************************************************************/
111 * AFS Cache Manager kernel thread
113 static int kafscmd(void *arg)
115 DECLARE_WAITQUEUE(myself, current);
117 struct rxrpc_call *call;
118 _SRXAFSCM_xxxx_t func;
119 int die;
121 printk("kAFS: Started kafscmd %d\n", current->pid);
123 daemonize("kafscmd");
125 complete(&kafscmd_alive);
127 /* loop around looking for things to attend to */
128 do {
129 if (list_empty(&kafscmd_attention_list)) {
130 set_current_state(TASK_INTERRUPTIBLE);
131 add_wait_queue(&kafscmd_sleepq, &myself);
133 for (;;) {
134 set_current_state(TASK_INTERRUPTIBLE);
135 if (!list_empty(&kafscmd_attention_list) ||
136 signal_pending(current) ||
137 kafscmd_die)
138 break;
140 schedule();
143 remove_wait_queue(&kafscmd_sleepq, &myself);
144 set_current_state(TASK_RUNNING);
147 die = kafscmd_die;
149 /* dequeue the next call requiring attention */
150 call = NULL;
151 spin_lock(&kafscmd_attention_lock);
153 if (!list_empty(&kafscmd_attention_list)) {
154 call = list_entry(kafscmd_attention_list.next,
155 struct rxrpc_call,
156 app_attn_link);
157 list_del_init(&call->app_attn_link);
158 die = 0;
161 spin_unlock(&kafscmd_attention_lock);
163 if (call) {
164 /* act upon it */
165 _debug("@@@ Begin Attend Call %p", call);
167 func = call->app_user;
168 if (func)
169 func(call);
171 rxrpc_put_call(call);
173 _debug("@@@ End Attend Call %p", call);
176 } while(!die);
178 /* and that's all */
179 complete_and_exit(&kafscmd_dead, 0);
181 } /* end kafscmd() */
183 /*****************************************************************************/
185 * handle a call coming in to the cache manager
186 * - if I want to keep the call, I must increment its usage count
187 * - the return value will be negated and passed back in an abort packet if
188 * non-zero
189 * - serialised by virtue of there only being one krxiod
191 static int afscm_new_call(struct rxrpc_call *call)
193 _enter("%p{cid=%u u=%d}",
194 call, ntohl(call->call_id), atomic_read(&call->usage));
196 rxrpc_get_call(call);
198 /* add to my current call list */
199 spin_lock(&afscm_calls_lock);
200 list_add(&call->app_link,&afscm_calls);
201 spin_unlock(&afscm_calls_lock);
203 _leave(" = 0");
204 return 0;
206 } /* end afscm_new_call() */
208 /*****************************************************************************/
210 * queue on the kafscmd queue for attention
212 static void afscm_attention(struct rxrpc_call *call)
214 _enter("%p{cid=%u u=%d}",
215 call, ntohl(call->call_id), atomic_read(&call->usage));
217 spin_lock(&kafscmd_attention_lock);
219 if (list_empty(&call->app_attn_link)) {
220 list_add_tail(&call->app_attn_link, &kafscmd_attention_list);
221 rxrpc_get_call(call);
224 spin_unlock(&kafscmd_attention_lock);
226 wake_up(&kafscmd_sleepq);
228 _leave(" {u=%d}", atomic_read(&call->usage));
229 } /* end afscm_attention() */
231 /*****************************************************************************/
233 * handle my call being aborted
234 * - clean up, dequeue and put my ref to the call
236 static void afscm_error(struct rxrpc_call *call)
238 int removed;
240 _enter("%p{est=%s ac=%u er=%d}",
241 call,
242 rxrpc_call_error_states[call->app_err_state],
243 call->app_abort_code,
244 call->app_errno);
246 spin_lock(&kafscmd_attention_lock);
248 if (list_empty(&call->app_attn_link)) {
249 list_add_tail(&call->app_attn_link, &kafscmd_attention_list);
250 rxrpc_get_call(call);
253 spin_unlock(&kafscmd_attention_lock);
255 removed = 0;
256 spin_lock(&afscm_calls_lock);
257 if (!list_empty(&call->app_link)) {
258 list_del_init(&call->app_link);
259 removed = 1;
261 spin_unlock(&afscm_calls_lock);
263 if (removed)
264 rxrpc_put_call(call);
266 wake_up(&kafscmd_sleepq);
268 _leave("");
269 } /* end afscm_error() */
271 /*****************************************************************************/
273 * map afs abort codes to/from Linux error codes
274 * - called with call->lock held
276 static void afscm_aemap(struct rxrpc_call *call)
278 switch (call->app_err_state) {
279 case RXRPC_ESTATE_LOCAL_ABORT:
280 call->app_abort_code = -call->app_errno;
281 break;
282 case RXRPC_ESTATE_PEER_ABORT:
283 call->app_errno = -ECONNABORTED;
284 break;
285 default:
286 break;
288 } /* end afscm_aemap() */
290 /*****************************************************************************/
292 * start the cache manager service if not already started
294 int afscm_start(void)
296 int ret;
298 down_write(&afscm_sem);
299 if (!afscm_usage) {
300 ret = kernel_thread(kafscmd, NULL, 0);
301 if (ret < 0)
302 goto out;
304 wait_for_completion(&kafscmd_alive);
306 ret = rxrpc_add_service(afs_transport, &AFSCM_service);
307 if (ret < 0)
308 goto kill;
310 afs_kafstimod_add_timer(&afs_mntpt_expiry_timer,
311 afs_mntpt_expiry_timeout * HZ);
314 afscm_usage++;
315 up_write(&afscm_sem);
317 return 0;
319 kill:
320 kafscmd_die = 1;
321 wake_up(&kafscmd_sleepq);
322 wait_for_completion(&kafscmd_dead);
324 out:
325 up_write(&afscm_sem);
326 return ret;
328 } /* end afscm_start() */
330 /*****************************************************************************/
332 * stop the cache manager service
334 void afscm_stop(void)
336 struct rxrpc_call *call;
338 down_write(&afscm_sem);
340 BUG_ON(afscm_usage == 0);
341 afscm_usage--;
343 if (afscm_usage == 0) {
344 /* don't want more incoming calls */
345 rxrpc_del_service(afs_transport, &AFSCM_service);
347 /* abort any calls I've still got open (the afscm_error() will
348 * dequeue them) */
349 spin_lock(&afscm_calls_lock);
350 while (!list_empty(&afscm_calls)) {
351 call = list_entry(afscm_calls.next,
352 struct rxrpc_call,
353 app_link);
355 list_del_init(&call->app_link);
356 rxrpc_get_call(call);
357 spin_unlock(&afscm_calls_lock);
359 rxrpc_call_abort(call, -ESRCH); /* abort, dequeue and
360 * put */
362 _debug("nuking active call %08x.%d",
363 ntohl(call->conn->conn_id),
364 ntohl(call->call_id));
365 rxrpc_put_call(call);
366 rxrpc_put_call(call);
368 spin_lock(&afscm_calls_lock);
370 spin_unlock(&afscm_calls_lock);
372 /* get rid of my daemon */
373 kafscmd_die = 1;
374 wake_up(&kafscmd_sleepq);
375 wait_for_completion(&kafscmd_dead);
377 /* dispose of any calls waiting for attention */
378 spin_lock(&kafscmd_attention_lock);
379 while (!list_empty(&kafscmd_attention_list)) {
380 call = list_entry(kafscmd_attention_list.next,
381 struct rxrpc_call,
382 app_attn_link);
384 list_del_init(&call->app_attn_link);
385 spin_unlock(&kafscmd_attention_lock);
387 rxrpc_put_call(call);
389 spin_lock(&kafscmd_attention_lock);
391 spin_unlock(&kafscmd_attention_lock);
393 afs_kafstimod_del_timer(&afs_mntpt_expiry_timer);
396 up_write(&afscm_sem);
398 } /* end afscm_stop() */
400 /*****************************************************************************/
402 * handle the fileserver breaking a set of callbacks
404 static void _SRXAFSCM_CallBack(struct rxrpc_call *call)
406 struct afs_server *server;
407 size_t count, qty, tmp;
408 int ret = 0, removed;
410 _enter("%p{acs=%s}", call, rxrpc_call_states[call->app_call_state]);
412 server = afs_server_get_from_peer(call->conn->peer);
414 switch (call->app_call_state) {
415 /* we've received the last packet
416 * - drain all the data from the call and send the reply
418 case RXRPC_CSTATE_SRVR_GOT_ARGS:
419 ret = -EBADMSG;
420 qty = call->app_ready_qty;
421 if (qty < 8 || qty > 50 * (6 * 4) + 8)
422 break;
425 struct afs_callback *cb, *pcb;
426 int loop;
427 __be32 *fp, *bp;
429 fp = rxrpc_call_alloc_scratch(call, qty);
431 /* drag the entire argument block out to the scratch
432 * space */
433 ret = rxrpc_call_read_data(call, fp, qty, 0);
434 if (ret < 0)
435 break;
437 /* and unmarshall the parameter block */
438 ret = -EBADMSG;
439 count = ntohl(*fp++);
440 if (count>AFSCBMAX ||
441 (count * (3 * 4) + 8 != qty &&
442 count * (6 * 4) + 8 != qty))
443 break;
445 bp = fp + count*3;
446 tmp = ntohl(*bp++);
447 if (tmp > 0 && tmp != count)
448 break;
449 if (tmp == 0)
450 bp = NULL;
452 pcb = cb = rxrpc_call_alloc_scratch_s(
453 call, struct afs_callback);
455 for (loop = count - 1; loop >= 0; loop--) {
456 pcb->fid.vid = ntohl(*fp++);
457 pcb->fid.vnode = ntohl(*fp++);
458 pcb->fid.unique = ntohl(*fp++);
459 if (bp) {
460 pcb->version = ntohl(*bp++);
461 pcb->expiry = ntohl(*bp++);
462 pcb->type = ntohl(*bp++);
464 else {
465 pcb->version = 0;
466 pcb->expiry = 0;
467 pcb->type = AFSCM_CB_UNTYPED;
469 pcb++;
472 /* invoke the actual service routine */
473 ret = SRXAFSCM_CallBack(server, count, cb);
474 if (ret < 0)
475 break;
478 /* send the reply */
479 ret = rxrpc_call_write_data(call, 0, NULL, RXRPC_LAST_PACKET,
480 GFP_KERNEL, 0, &count);
481 if (ret < 0)
482 break;
483 break;
485 /* operation complete */
486 case RXRPC_CSTATE_COMPLETE:
487 call->app_user = NULL;
488 removed = 0;
489 spin_lock(&afscm_calls_lock);
490 if (!list_empty(&call->app_link)) {
491 list_del_init(&call->app_link);
492 removed = 1;
494 spin_unlock(&afscm_calls_lock);
496 if (removed)
497 rxrpc_put_call(call);
498 break;
500 /* operation terminated on error */
501 case RXRPC_CSTATE_ERROR:
502 call->app_user = NULL;
503 break;
505 default:
506 break;
509 if (ret < 0)
510 rxrpc_call_abort(call, ret);
512 afs_put_server(server);
514 _leave(" = %d", ret);
516 } /* end _SRXAFSCM_CallBack() */
518 /*****************************************************************************/
520 * handle the fileserver asking us to initialise our callback state
522 static void _SRXAFSCM_InitCallBackState(struct rxrpc_call *call)
524 struct afs_server *server;
525 size_t count;
526 int ret = 0, removed;
528 _enter("%p{acs=%s}", call, rxrpc_call_states[call->app_call_state]);
530 server = afs_server_get_from_peer(call->conn->peer);
532 switch (call->app_call_state) {
533 /* we've received the last packet - drain all the data from the
534 * call */
535 case RXRPC_CSTATE_SRVR_GOT_ARGS:
536 /* shouldn't be any args */
537 ret = -EBADMSG;
538 break;
540 /* send the reply when asked for it */
541 case RXRPC_CSTATE_SRVR_SND_REPLY:
542 /* invoke the actual service routine */
543 ret = SRXAFSCM_InitCallBackState(server);
544 if (ret < 0)
545 break;
547 ret = rxrpc_call_write_data(call, 0, NULL, RXRPC_LAST_PACKET,
548 GFP_KERNEL, 0, &count);
549 if (ret < 0)
550 break;
551 break;
553 /* operation complete */
554 case RXRPC_CSTATE_COMPLETE:
555 call->app_user = NULL;
556 removed = 0;
557 spin_lock(&afscm_calls_lock);
558 if (!list_empty(&call->app_link)) {
559 list_del_init(&call->app_link);
560 removed = 1;
562 spin_unlock(&afscm_calls_lock);
564 if (removed)
565 rxrpc_put_call(call);
566 break;
568 /* operation terminated on error */
569 case RXRPC_CSTATE_ERROR:
570 call->app_user = NULL;
571 break;
573 default:
574 break;
577 if (ret < 0)
578 rxrpc_call_abort(call, ret);
580 afs_put_server(server);
582 _leave(" = %d", ret);
584 } /* end _SRXAFSCM_InitCallBackState() */
586 /*****************************************************************************/
588 * handle a probe from a fileserver
590 static void _SRXAFSCM_Probe(struct rxrpc_call *call)
592 struct afs_server *server;
593 size_t count;
594 int ret = 0, removed;
596 _enter("%p{acs=%s}", call, rxrpc_call_states[call->app_call_state]);
598 server = afs_server_get_from_peer(call->conn->peer);
600 switch (call->app_call_state) {
601 /* we've received the last packet - drain all the data from the
602 * call */
603 case RXRPC_CSTATE_SRVR_GOT_ARGS:
604 /* shouldn't be any args */
605 ret = -EBADMSG;
606 break;
608 /* send the reply when asked for it */
609 case RXRPC_CSTATE_SRVR_SND_REPLY:
610 /* invoke the actual service routine */
611 ret = SRXAFSCM_Probe(server);
612 if (ret < 0)
613 break;
615 ret = rxrpc_call_write_data(call, 0, NULL, RXRPC_LAST_PACKET,
616 GFP_KERNEL, 0, &count);
617 if (ret < 0)
618 break;
619 break;
621 /* operation complete */
622 case RXRPC_CSTATE_COMPLETE:
623 call->app_user = NULL;
624 removed = 0;
625 spin_lock(&afscm_calls_lock);
626 if (!list_empty(&call->app_link)) {
627 list_del_init(&call->app_link);
628 removed = 1;
630 spin_unlock(&afscm_calls_lock);
632 if (removed)
633 rxrpc_put_call(call);
634 break;
636 /* operation terminated on error */
637 case RXRPC_CSTATE_ERROR:
638 call->app_user = NULL;
639 break;
641 default:
642 break;
645 if (ret < 0)
646 rxrpc_call_abort(call, ret);
648 afs_put_server(server);
650 _leave(" = %d", ret);
652 } /* end _SRXAFSCM_Probe() */