xref: /linux/fs/afs/cmservice.c (revision 4e0385dd7469d933c4adf84a617f872ca547aa07)
1 /* AFS Cache Manager Service
2  *
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>
13 #include <linux/init.h>
14 #include <linux/slab.h>
15 #include <linux/sched.h>
16 #include <linux/ip.h>
17 #include "internal.h"
18 #include "afs_cm.h"
19 
20 static int afs_deliver_cb_init_call_back_state(struct afs_call *);
21 static int afs_deliver_cb_init_call_back_state3(struct afs_call *);
22 static int afs_deliver_cb_probe(struct afs_call *);
23 static int afs_deliver_cb_callback(struct afs_call *);
24 static int afs_deliver_cb_probe_uuid(struct afs_call *);
25 static int afs_deliver_cb_tell_me_about_yourself(struct afs_call *);
26 static void afs_cm_destructor(struct afs_call *);
27 static void SRXAFSCB_CallBack(struct work_struct *);
28 static void SRXAFSCB_InitCallBackState(struct work_struct *);
29 static void SRXAFSCB_Probe(struct work_struct *);
30 static void SRXAFSCB_ProbeUuid(struct work_struct *);
31 static void SRXAFSCB_TellMeAboutYourself(struct work_struct *);
32 
33 #define CM_NAME(name) \
34 	const char afs_SRXCB##name##_name[] __tracepoint_string =	\
35 		"CB." #name
36 
37 /*
38  * CB.CallBack operation type
39  */
40 static CM_NAME(CallBack);
41 static const struct afs_call_type afs_SRXCBCallBack = {
42 	.name		= afs_SRXCBCallBack_name,
43 	.deliver	= afs_deliver_cb_callback,
44 	.abort_to_error	= afs_abort_to_error,
45 	.destructor	= afs_cm_destructor,
46 	.work		= SRXAFSCB_CallBack,
47 };
48 
49 /*
50  * CB.InitCallBackState operation type
51  */
52 static CM_NAME(InitCallBackState);
53 static const struct afs_call_type afs_SRXCBInitCallBackState = {
54 	.name		= afs_SRXCBInitCallBackState_name,
55 	.deliver	= afs_deliver_cb_init_call_back_state,
56 	.abort_to_error	= afs_abort_to_error,
57 	.destructor	= afs_cm_destructor,
58 	.work		= SRXAFSCB_InitCallBackState,
59 };
60 
61 /*
62  * CB.InitCallBackState3 operation type
63  */
64 static CM_NAME(InitCallBackState3);
65 static const struct afs_call_type afs_SRXCBInitCallBackState3 = {
66 	.name		= afs_SRXCBInitCallBackState3_name,
67 	.deliver	= afs_deliver_cb_init_call_back_state3,
68 	.abort_to_error	= afs_abort_to_error,
69 	.destructor	= afs_cm_destructor,
70 	.work		= SRXAFSCB_InitCallBackState,
71 };
72 
73 /*
74  * CB.Probe operation type
75  */
76 static CM_NAME(Probe);
77 static const struct afs_call_type afs_SRXCBProbe = {
78 	.name		= afs_SRXCBProbe_name,
79 	.deliver	= afs_deliver_cb_probe,
80 	.abort_to_error	= afs_abort_to_error,
81 	.destructor	= afs_cm_destructor,
82 	.work		= SRXAFSCB_Probe,
83 };
84 
85 /*
86  * CB.ProbeUuid operation type
87  */
88 static CM_NAME(ProbeUuid);
89 static const struct afs_call_type afs_SRXCBProbeUuid = {
90 	.name		= afs_SRXCBProbeUuid_name,
91 	.deliver	= afs_deliver_cb_probe_uuid,
92 	.abort_to_error	= afs_abort_to_error,
93 	.destructor	= afs_cm_destructor,
94 	.work		= SRXAFSCB_ProbeUuid,
95 };
96 
97 /*
98  * CB.TellMeAboutYourself operation type
99  */
100 static CM_NAME(TellMeAboutYourself);
101 static const struct afs_call_type afs_SRXCBTellMeAboutYourself = {
102 	.name		= afs_SRXCBTellMeAboutYourself_name,
103 	.deliver	= afs_deliver_cb_tell_me_about_yourself,
104 	.abort_to_error	= afs_abort_to_error,
105 	.destructor	= afs_cm_destructor,
106 	.work		= SRXAFSCB_TellMeAboutYourself,
107 };
108 
109 /*
110  * route an incoming cache manager call
111  * - return T if supported, F if not
112  */
113 bool afs_cm_incoming_call(struct afs_call *call)
114 {
115 	_enter("{CB.OP %u}", call->operation_ID);
116 
117 	switch (call->operation_ID) {
118 	case CBCallBack:
119 		call->type = &afs_SRXCBCallBack;
120 		return true;
121 	case CBInitCallBackState:
122 		call->type = &afs_SRXCBInitCallBackState;
123 		return true;
124 	case CBInitCallBackState3:
125 		call->type = &afs_SRXCBInitCallBackState3;
126 		return true;
127 	case CBProbe:
128 		call->type = &afs_SRXCBProbe;
129 		return true;
130 	case CBTellMeAboutYourself:
131 		call->type = &afs_SRXCBTellMeAboutYourself;
132 		return true;
133 	default:
134 		return false;
135 	}
136 }
137 
138 /*
139  * clean up a cache manager call
140  */
141 static void afs_cm_destructor(struct afs_call *call)
142 {
143 	_enter("");
144 
145 	/* Break the callbacks here so that we do it after the final ACK is
146 	 * received.  The step number here must match the final number in
147 	 * afs_deliver_cb_callback().
148 	 */
149 	if (call->unmarshall == 5) {
150 		ASSERT(call->server && call->count && call->request);
151 		afs_break_callbacks(call->server, call->count, call->request);
152 	}
153 
154 	afs_put_server(call->server);
155 	call->server = NULL;
156 	kfree(call->buffer);
157 	call->buffer = NULL;
158 }
159 
160 /*
161  * allow the fileserver to see if the cache manager is still alive
162  */
163 static void SRXAFSCB_CallBack(struct work_struct *work)
164 {
165 	struct afs_call *call = container_of(work, struct afs_call, work);
166 
167 	_enter("");
168 
169 	/* be sure to send the reply *before* attempting to spam the AFS server
170 	 * with FSFetchStatus requests on the vnodes with broken callbacks lest
171 	 * the AFS server get into a vicious cycle of trying to break further
172 	 * callbacks because it hadn't received completion of the CBCallBack op
173 	 * yet */
174 	afs_send_empty_reply(call);
175 
176 	afs_break_callbacks(call->server, call->count, call->request);
177 	afs_put_call(call);
178 	_leave("");
179 }
180 
181 /*
182  * deliver request data to a CB.CallBack call
183  */
184 static int afs_deliver_cb_callback(struct afs_call *call)
185 {
186 	struct sockaddr_rxrpc srx;
187 	struct afs_callback *cb;
188 	struct afs_server *server;
189 	__be32 *bp;
190 	u32 tmp;
191 	int ret, loop;
192 
193 	_enter("{%u}", call->unmarshall);
194 
195 	switch (call->unmarshall) {
196 	case 0:
197 		rxrpc_kernel_get_peer(afs_socket, call->rxcall, &srx);
198 		call->offset = 0;
199 		call->unmarshall++;
200 
201 		/* extract the FID array and its count in two steps */
202 	case 1:
203 		_debug("extract FID count");
204 		ret = afs_extract_data(call, &call->tmp, 4, true);
205 		if (ret < 0)
206 			return ret;
207 
208 		call->count = ntohl(call->tmp);
209 		_debug("FID count: %u", call->count);
210 		if (call->count > AFSCBMAX)
211 			return -EBADMSG;
212 
213 		call->buffer = kmalloc(call->count * 3 * 4, GFP_KERNEL);
214 		if (!call->buffer)
215 			return -ENOMEM;
216 		call->offset = 0;
217 		call->unmarshall++;
218 
219 	case 2:
220 		_debug("extract FID array");
221 		ret = afs_extract_data(call, call->buffer,
222 				       call->count * 3 * 4, true);
223 		if (ret < 0)
224 			return ret;
225 
226 		_debug("unmarshall FID array");
227 		call->request = kcalloc(call->count,
228 					sizeof(struct afs_callback),
229 					GFP_KERNEL);
230 		if (!call->request)
231 			return -ENOMEM;
232 
233 		cb = call->request;
234 		bp = call->buffer;
235 		for (loop = call->count; loop > 0; loop--, cb++) {
236 			cb->fid.vid	= ntohl(*bp++);
237 			cb->fid.vnode	= ntohl(*bp++);
238 			cb->fid.unique	= ntohl(*bp++);
239 			cb->type	= AFSCM_CB_UNTYPED;
240 		}
241 
242 		call->offset = 0;
243 		call->unmarshall++;
244 
245 		/* extract the callback array and its count in two steps */
246 	case 3:
247 		_debug("extract CB count");
248 		ret = afs_extract_data(call, &call->tmp, 4, true);
249 		if (ret < 0)
250 			return ret;
251 
252 		tmp = ntohl(call->tmp);
253 		_debug("CB count: %u", tmp);
254 		if (tmp != call->count && tmp != 0)
255 			return -EBADMSG;
256 		call->offset = 0;
257 		call->unmarshall++;
258 
259 	case 4:
260 		_debug("extract CB array");
261 		ret = afs_extract_data(call, call->buffer,
262 				       call->count * 3 * 4, false);
263 		if (ret < 0)
264 			return ret;
265 
266 		_debug("unmarshall CB array");
267 		cb = call->request;
268 		bp = call->buffer;
269 		for (loop = call->count; loop > 0; loop--, cb++) {
270 			cb->version	= ntohl(*bp++);
271 			cb->expiry	= ntohl(*bp++);
272 			cb->type	= ntohl(*bp++);
273 		}
274 
275 		call->offset = 0;
276 		call->unmarshall++;
277 
278 		/* Record that the message was unmarshalled successfully so
279 		 * that the call destructor can know do the callback breaking
280 		 * work, even if the final ACK isn't received.
281 		 *
282 		 * If the step number changes, then afs_cm_destructor() must be
283 		 * updated also.
284 		 */
285 		call->unmarshall++;
286 	case 5:
287 		break;
288 	}
289 
290 	call->state = AFS_CALL_REPLYING;
291 
292 	/* we'll need the file server record as that tells us which set of
293 	 * vnodes to operate upon */
294 	server = afs_find_server(&srx);
295 	if (!server)
296 		return -ENOTCONN;
297 	call->server = server;
298 
299 	return afs_queue_call_work(call);
300 }
301 
302 /*
303  * allow the fileserver to request callback state (re-)initialisation
304  */
305 static void SRXAFSCB_InitCallBackState(struct work_struct *work)
306 {
307 	struct afs_call *call = container_of(work, struct afs_call, work);
308 
309 	_enter("{%p}", call->server);
310 
311 	afs_init_callback_state(call->server);
312 	afs_send_empty_reply(call);
313 	afs_put_call(call);
314 	_leave("");
315 }
316 
317 /*
318  * deliver request data to a CB.InitCallBackState call
319  */
320 static int afs_deliver_cb_init_call_back_state(struct afs_call *call)
321 {
322 	struct sockaddr_rxrpc srx;
323 	struct afs_server *server;
324 	int ret;
325 
326 	_enter("");
327 
328 	rxrpc_kernel_get_peer(afs_socket, call->rxcall, &srx);
329 
330 	ret = afs_extract_data(call, NULL, 0, false);
331 	if (ret < 0)
332 		return ret;
333 
334 	/* no unmarshalling required */
335 	call->state = AFS_CALL_REPLYING;
336 
337 	/* we'll need the file server record as that tells us which set of
338 	 * vnodes to operate upon */
339 	server = afs_find_server(&srx);
340 	if (!server)
341 		return -ENOTCONN;
342 	call->server = server;
343 
344 	return afs_queue_call_work(call);
345 }
346 
347 /*
348  * deliver request data to a CB.InitCallBackState3 call
349  */
350 static int afs_deliver_cb_init_call_back_state3(struct afs_call *call)
351 {
352 	struct sockaddr_rxrpc srx;
353 	struct afs_server *server;
354 	struct uuid_v1 *r;
355 	unsigned loop;
356 	__be32 *b;
357 	int ret;
358 
359 	_enter("");
360 
361 	rxrpc_kernel_get_peer(afs_socket, call->rxcall, &srx);
362 
363 	_enter("{%u}", call->unmarshall);
364 
365 	switch (call->unmarshall) {
366 	case 0:
367 		call->offset = 0;
368 		call->buffer = kmalloc(11 * sizeof(__be32), GFP_KERNEL);
369 		if (!call->buffer)
370 			return -ENOMEM;
371 		call->unmarshall++;
372 
373 	case 1:
374 		_debug("extract UUID");
375 		ret = afs_extract_data(call, call->buffer,
376 				       11 * sizeof(__be32), false);
377 		switch (ret) {
378 		case 0:		break;
379 		case -EAGAIN:	return 0;
380 		default:	return ret;
381 		}
382 
383 		_debug("unmarshall UUID");
384 		call->request = kmalloc(sizeof(struct uuid_v1), GFP_KERNEL);
385 		if (!call->request)
386 			return -ENOMEM;
387 
388 		b = call->buffer;
389 		r = call->request;
390 		r->time_low			= b[0];
391 		r->time_mid			= htons(ntohl(b[1]));
392 		r->time_hi_and_version		= htons(ntohl(b[2]));
393 		r->clock_seq_hi_and_reserved 	= ntohl(b[3]);
394 		r->clock_seq_low		= ntohl(b[4]);
395 
396 		for (loop = 0; loop < 6; loop++)
397 			r->node[loop] = ntohl(b[loop + 5]);
398 
399 		call->offset = 0;
400 		call->unmarshall++;
401 
402 	case 2:
403 		break;
404 	}
405 
406 	/* no unmarshalling required */
407 	call->state = AFS_CALL_REPLYING;
408 
409 	/* we'll need the file server record as that tells us which set of
410 	 * vnodes to operate upon */
411 	server = afs_find_server(&srx);
412 	if (!server)
413 		return -ENOTCONN;
414 	call->server = server;
415 
416 	return afs_queue_call_work(call);
417 }
418 
419 /*
420  * allow the fileserver to see if the cache manager is still alive
421  */
422 static void SRXAFSCB_Probe(struct work_struct *work)
423 {
424 	struct afs_call *call = container_of(work, struct afs_call, work);
425 
426 	_enter("");
427 	afs_send_empty_reply(call);
428 	afs_put_call(call);
429 	_leave("");
430 }
431 
432 /*
433  * deliver request data to a CB.Probe call
434  */
435 static int afs_deliver_cb_probe(struct afs_call *call)
436 {
437 	int ret;
438 
439 	_enter("");
440 
441 	ret = afs_extract_data(call, NULL, 0, false);
442 	if (ret < 0)
443 		return ret;
444 
445 	/* no unmarshalling required */
446 	call->state = AFS_CALL_REPLYING;
447 
448 	return afs_queue_call_work(call);
449 }
450 
451 /*
452  * allow the fileserver to quickly find out if the fileserver has been rebooted
453  */
454 static void SRXAFSCB_ProbeUuid(struct work_struct *work)
455 {
456 	struct afs_call *call = container_of(work, struct afs_call, work);
457 	struct uuid_v1 *r = call->request;
458 
459 	struct {
460 		__be32	match;
461 	} reply;
462 
463 	_enter("");
464 
465 	if (memcmp(r, &afs_uuid, sizeof(afs_uuid)) == 0)
466 		reply.match = htonl(0);
467 	else
468 		reply.match = htonl(1);
469 
470 	afs_send_simple_reply(call, &reply, sizeof(reply));
471 	afs_put_call(call);
472 	_leave("");
473 }
474 
475 /*
476  * deliver request data to a CB.ProbeUuid call
477  */
478 static int afs_deliver_cb_probe_uuid(struct afs_call *call)
479 {
480 	struct uuid_v1 *r;
481 	unsigned loop;
482 	__be32 *b;
483 	int ret;
484 
485 	_enter("{%u}", call->unmarshall);
486 
487 	switch (call->unmarshall) {
488 	case 0:
489 		call->offset = 0;
490 		call->buffer = kmalloc(11 * sizeof(__be32), GFP_KERNEL);
491 		if (!call->buffer)
492 			return -ENOMEM;
493 		call->unmarshall++;
494 
495 	case 1:
496 		_debug("extract UUID");
497 		ret = afs_extract_data(call, call->buffer,
498 				       11 * sizeof(__be32), false);
499 		switch (ret) {
500 		case 0:		break;
501 		case -EAGAIN:	return 0;
502 		default:	return ret;
503 		}
504 
505 		_debug("unmarshall UUID");
506 		call->request = kmalloc(sizeof(struct uuid_v1), GFP_KERNEL);
507 		if (!call->request)
508 			return -ENOMEM;
509 
510 		b = call->buffer;
511 		r = call->request;
512 		r->time_low			= b[0];
513 		r->time_mid			= htons(ntohl(b[1]));
514 		r->time_hi_and_version		= htons(ntohl(b[2]));
515 		r->clock_seq_hi_and_reserved 	= ntohl(b[3]);
516 		r->clock_seq_low		= ntohl(b[4]);
517 
518 		for (loop = 0; loop < 6; loop++)
519 			r->node[loop] = ntohl(b[loop + 5]);
520 
521 		call->offset = 0;
522 		call->unmarshall++;
523 
524 	case 2:
525 		break;
526 	}
527 
528 	call->state = AFS_CALL_REPLYING;
529 
530 	return afs_queue_call_work(call);
531 }
532 
533 /*
534  * allow the fileserver to ask about the cache manager's capabilities
535  */
536 static void SRXAFSCB_TellMeAboutYourself(struct work_struct *work)
537 {
538 	struct afs_interface *ifs;
539 	struct afs_call *call = container_of(work, struct afs_call, work);
540 	int loop, nifs;
541 
542 	struct {
543 		struct /* InterfaceAddr */ {
544 			__be32 nifs;
545 			__be32 uuid[11];
546 			__be32 ifaddr[32];
547 			__be32 netmask[32];
548 			__be32 mtu[32];
549 		} ia;
550 		struct /* Capabilities */ {
551 			__be32 capcount;
552 			__be32 caps[1];
553 		} cap;
554 	} reply;
555 
556 	_enter("");
557 
558 	nifs = 0;
559 	ifs = kcalloc(32, sizeof(*ifs), GFP_KERNEL);
560 	if (ifs) {
561 		nifs = afs_get_ipv4_interfaces(ifs, 32, false);
562 		if (nifs < 0) {
563 			kfree(ifs);
564 			ifs = NULL;
565 			nifs = 0;
566 		}
567 	}
568 
569 	memset(&reply, 0, sizeof(reply));
570 	reply.ia.nifs = htonl(nifs);
571 
572 	reply.ia.uuid[0] = afs_uuid.time_low;
573 	reply.ia.uuid[1] = htonl(ntohs(afs_uuid.time_mid));
574 	reply.ia.uuid[2] = htonl(ntohs(afs_uuid.time_hi_and_version));
575 	reply.ia.uuid[3] = htonl((s8) afs_uuid.clock_seq_hi_and_reserved);
576 	reply.ia.uuid[4] = htonl((s8) afs_uuid.clock_seq_low);
577 	for (loop = 0; loop < 6; loop++)
578 		reply.ia.uuid[loop + 5] = htonl((s8) afs_uuid.node[loop]);
579 
580 	if (ifs) {
581 		for (loop = 0; loop < nifs; loop++) {
582 			reply.ia.ifaddr[loop] = ifs[loop].address.s_addr;
583 			reply.ia.netmask[loop] = ifs[loop].netmask.s_addr;
584 			reply.ia.mtu[loop] = htonl(ifs[loop].mtu);
585 		}
586 		kfree(ifs);
587 	}
588 
589 	reply.cap.capcount = htonl(1);
590 	reply.cap.caps[0] = htonl(AFS_CAP_ERROR_TRANSLATION);
591 	afs_send_simple_reply(call, &reply, sizeof(reply));
592 	afs_put_call(call);
593 	_leave("");
594 }
595 
596 /*
597  * deliver request data to a CB.TellMeAboutYourself call
598  */
599 static int afs_deliver_cb_tell_me_about_yourself(struct afs_call *call)
600 {
601 	int ret;
602 
603 	_enter("");
604 
605 	ret = afs_extract_data(call, NULL, 0, false);
606 	if (ret < 0)
607 		return ret;
608 
609 	/* no unmarshalling required */
610 	call->state = AFS_CALL_REPLYING;
611 
612 	return afs_queue_call_work(call);
613 }
614