xref: /openbmc/linux/fs/afs/cmservice.c (revision 8e8d7f13b6d5a93b3d2cf9a4ceaaf923809fd5ac)
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 
28 #define CM_NAME(name) \
29 	const char afs_SRXCB##name##_name[] __tracepoint_string =	\
30 		"CB." #name
31 
32 /*
33  * CB.CallBack operation type
34  */
35 static CM_NAME(CallBack);
36 static const struct afs_call_type afs_SRXCBCallBack = {
37 	.name		= afs_SRXCBCallBack_name,
38 	.deliver	= afs_deliver_cb_callback,
39 	.abort_to_error	= afs_abort_to_error,
40 	.destructor	= afs_cm_destructor,
41 };
42 
43 /*
44  * CB.InitCallBackState operation type
45  */
46 static CM_NAME(InitCallBackState);
47 static const struct afs_call_type afs_SRXCBInitCallBackState = {
48 	.name		= afs_SRXCBInitCallBackState_name,
49 	.deliver	= afs_deliver_cb_init_call_back_state,
50 	.abort_to_error	= afs_abort_to_error,
51 	.destructor	= afs_cm_destructor,
52 };
53 
54 /*
55  * CB.InitCallBackState3 operation type
56  */
57 static CM_NAME(InitCallBackState3);
58 static const struct afs_call_type afs_SRXCBInitCallBackState3 = {
59 	.name		= afs_SRXCBInitCallBackState3_name,
60 	.deliver	= afs_deliver_cb_init_call_back_state3,
61 	.abort_to_error	= afs_abort_to_error,
62 	.destructor	= afs_cm_destructor,
63 };
64 
65 /*
66  * CB.Probe operation type
67  */
68 static CM_NAME(Probe);
69 static const struct afs_call_type afs_SRXCBProbe = {
70 	.name		= afs_SRXCBProbe_name,
71 	.deliver	= afs_deliver_cb_probe,
72 	.abort_to_error	= afs_abort_to_error,
73 	.destructor	= afs_cm_destructor,
74 };
75 
76 /*
77  * CB.ProbeUuid operation type
78  */
79 static CM_NAME(ProbeUuid);
80 static const struct afs_call_type afs_SRXCBProbeUuid = {
81 	.name		= afs_SRXCBProbeUuid_name,
82 	.deliver	= afs_deliver_cb_probe_uuid,
83 	.abort_to_error	= afs_abort_to_error,
84 	.destructor	= afs_cm_destructor,
85 };
86 
87 /*
88  * CB.TellMeAboutYourself operation type
89  */
90 static CM_NAME(TellMeAboutYourself);
91 static const struct afs_call_type afs_SRXCBTellMeAboutYourself = {
92 	.name		= afs_SRXCBTellMeAboutYourself_name,
93 	.deliver	= afs_deliver_cb_tell_me_about_yourself,
94 	.abort_to_error	= afs_abort_to_error,
95 	.destructor	= afs_cm_destructor,
96 };
97 
98 /*
99  * route an incoming cache manager call
100  * - return T if supported, F if not
101  */
102 bool afs_cm_incoming_call(struct afs_call *call)
103 {
104 	_enter("{CB.OP %u}", call->operation_ID);
105 
106 	switch (call->operation_ID) {
107 	case CBCallBack:
108 		call->type = &afs_SRXCBCallBack;
109 		return true;
110 	case CBInitCallBackState:
111 		call->type = &afs_SRXCBInitCallBackState;
112 		return true;
113 	case CBInitCallBackState3:
114 		call->type = &afs_SRXCBInitCallBackState3;
115 		return true;
116 	case CBProbe:
117 		call->type = &afs_SRXCBProbe;
118 		return true;
119 	case CBTellMeAboutYourself:
120 		call->type = &afs_SRXCBTellMeAboutYourself;
121 		return true;
122 	default:
123 		return false;
124 	}
125 }
126 
127 /*
128  * clean up a cache manager call
129  */
130 static void afs_cm_destructor(struct afs_call *call)
131 {
132 	_enter("");
133 
134 	/* Break the callbacks here so that we do it after the final ACK is
135 	 * received.  The step number here must match the final number in
136 	 * afs_deliver_cb_callback().
137 	 */
138 	if (call->unmarshall == 5) {
139 		ASSERT(call->server && call->count && call->request);
140 		afs_break_callbacks(call->server, call->count, call->request);
141 	}
142 
143 	afs_put_server(call->server);
144 	call->server = NULL;
145 	kfree(call->buffer);
146 	call->buffer = NULL;
147 }
148 
149 /*
150  * allow the fileserver to see if the cache manager is still alive
151  */
152 static void SRXAFSCB_CallBack(struct work_struct *work)
153 {
154 	struct afs_call *call = container_of(work, struct afs_call, work);
155 
156 	_enter("");
157 
158 	/* be sure to send the reply *before* attempting to spam the AFS server
159 	 * with FSFetchStatus requests on the vnodes with broken callbacks lest
160 	 * the AFS server get into a vicious cycle of trying to break further
161 	 * callbacks because it hadn't received completion of the CBCallBack op
162 	 * yet */
163 	afs_send_empty_reply(call);
164 
165 	afs_break_callbacks(call->server, call->count, call->request);
166 	_leave("");
167 }
168 
169 /*
170  * deliver request data to a CB.CallBack call
171  */
172 static int afs_deliver_cb_callback(struct afs_call *call)
173 {
174 	struct sockaddr_rxrpc srx;
175 	struct afs_callback *cb;
176 	struct afs_server *server;
177 	__be32 *bp;
178 	u32 tmp;
179 	int ret, loop;
180 
181 	_enter("{%u}", call->unmarshall);
182 
183 	switch (call->unmarshall) {
184 	case 0:
185 		rxrpc_kernel_get_peer(afs_socket, call->rxcall, &srx);
186 		call->offset = 0;
187 		call->unmarshall++;
188 
189 		/* extract the FID array and its count in two steps */
190 	case 1:
191 		_debug("extract FID count");
192 		ret = afs_extract_data(call, &call->tmp, 4, true);
193 		if (ret < 0)
194 			return ret;
195 
196 		call->count = ntohl(call->tmp);
197 		_debug("FID count: %u", call->count);
198 		if (call->count > AFSCBMAX)
199 			return -EBADMSG;
200 
201 		call->buffer = kmalloc(call->count * 3 * 4, GFP_KERNEL);
202 		if (!call->buffer)
203 			return -ENOMEM;
204 		call->offset = 0;
205 		call->unmarshall++;
206 
207 	case 2:
208 		_debug("extract FID array");
209 		ret = afs_extract_data(call, call->buffer,
210 				       call->count * 3 * 4, true);
211 		if (ret < 0)
212 			return ret;
213 
214 		_debug("unmarshall FID array");
215 		call->request = kcalloc(call->count,
216 					sizeof(struct afs_callback),
217 					GFP_KERNEL);
218 		if (!call->request)
219 			return -ENOMEM;
220 
221 		cb = call->request;
222 		bp = call->buffer;
223 		for (loop = call->count; loop > 0; loop--, cb++) {
224 			cb->fid.vid	= ntohl(*bp++);
225 			cb->fid.vnode	= ntohl(*bp++);
226 			cb->fid.unique	= ntohl(*bp++);
227 			cb->type	= AFSCM_CB_UNTYPED;
228 		}
229 
230 		call->offset = 0;
231 		call->unmarshall++;
232 
233 		/* extract the callback array and its count in two steps */
234 	case 3:
235 		_debug("extract CB count");
236 		ret = afs_extract_data(call, &call->tmp, 4, true);
237 		if (ret < 0)
238 			return ret;
239 
240 		tmp = ntohl(call->tmp);
241 		_debug("CB count: %u", tmp);
242 		if (tmp != call->count && tmp != 0)
243 			return -EBADMSG;
244 		call->offset = 0;
245 		call->unmarshall++;
246 
247 	case 4:
248 		_debug("extract CB array");
249 		ret = afs_extract_data(call, call->buffer,
250 				       call->count * 3 * 4, false);
251 		if (ret < 0)
252 			return ret;
253 
254 		_debug("unmarshall CB array");
255 		cb = call->request;
256 		bp = call->buffer;
257 		for (loop = call->count; loop > 0; loop--, cb++) {
258 			cb->version	= ntohl(*bp++);
259 			cb->expiry	= ntohl(*bp++);
260 			cb->type	= ntohl(*bp++);
261 		}
262 
263 		call->offset = 0;
264 		call->unmarshall++;
265 
266 		/* Record that the message was unmarshalled successfully so
267 		 * that the call destructor can know do the callback breaking
268 		 * work, even if the final ACK isn't received.
269 		 *
270 		 * If the step number changes, then afs_cm_destructor() must be
271 		 * updated also.
272 		 */
273 		call->unmarshall++;
274 	case 5:
275 		break;
276 	}
277 
278 	call->state = AFS_CALL_REPLYING;
279 
280 	/* we'll need the file server record as that tells us which set of
281 	 * vnodes to operate upon */
282 	server = afs_find_server(&srx);
283 	if (!server)
284 		return -ENOTCONN;
285 	call->server = server;
286 
287 	INIT_WORK(&call->work, SRXAFSCB_CallBack);
288 	queue_work(afs_wq, &call->work);
289 	return 0;
290 }
291 
292 /*
293  * allow the fileserver to request callback state (re-)initialisation
294  */
295 static void SRXAFSCB_InitCallBackState(struct work_struct *work)
296 {
297 	struct afs_call *call = container_of(work, struct afs_call, work);
298 
299 	_enter("{%p}", call->server);
300 
301 	afs_init_callback_state(call->server);
302 	afs_send_empty_reply(call);
303 	_leave("");
304 }
305 
306 /*
307  * deliver request data to a CB.InitCallBackState call
308  */
309 static int afs_deliver_cb_init_call_back_state(struct afs_call *call)
310 {
311 	struct sockaddr_rxrpc srx;
312 	struct afs_server *server;
313 	int ret;
314 
315 	_enter("");
316 
317 	rxrpc_kernel_get_peer(afs_socket, call->rxcall, &srx);
318 
319 	ret = afs_extract_data(call, NULL, 0, false);
320 	if (ret < 0)
321 		return ret;
322 
323 	/* no unmarshalling required */
324 	call->state = AFS_CALL_REPLYING;
325 
326 	/* we'll need the file server record as that tells us which set of
327 	 * vnodes to operate upon */
328 	server = afs_find_server(&srx);
329 	if (!server)
330 		return -ENOTCONN;
331 	call->server = server;
332 
333 	INIT_WORK(&call->work, SRXAFSCB_InitCallBackState);
334 	queue_work(afs_wq, &call->work);
335 	return 0;
336 }
337 
338 /*
339  * deliver request data to a CB.InitCallBackState3 call
340  */
341 static int afs_deliver_cb_init_call_back_state3(struct afs_call *call)
342 {
343 	struct sockaddr_rxrpc srx;
344 	struct afs_server *server;
345 	struct afs_uuid *r;
346 	unsigned loop;
347 	__be32 *b;
348 	int ret;
349 
350 	_enter("");
351 
352 	rxrpc_kernel_get_peer(afs_socket, call->rxcall, &srx);
353 
354 	_enter("{%u}", call->unmarshall);
355 
356 	switch (call->unmarshall) {
357 	case 0:
358 		call->offset = 0;
359 		call->buffer = kmalloc(11 * sizeof(__be32), GFP_KERNEL);
360 		if (!call->buffer)
361 			return -ENOMEM;
362 		call->unmarshall++;
363 
364 	case 1:
365 		_debug("extract UUID");
366 		ret = afs_extract_data(call, call->buffer,
367 				       11 * sizeof(__be32), false);
368 		switch (ret) {
369 		case 0:		break;
370 		case -EAGAIN:	return 0;
371 		default:	return ret;
372 		}
373 
374 		_debug("unmarshall UUID");
375 		call->request = kmalloc(sizeof(struct afs_uuid), GFP_KERNEL);
376 		if (!call->request)
377 			return -ENOMEM;
378 
379 		b = call->buffer;
380 		r = call->request;
381 		r->time_low			= ntohl(b[0]);
382 		r->time_mid			= ntohl(b[1]);
383 		r->time_hi_and_version		= ntohl(b[2]);
384 		r->clock_seq_hi_and_reserved 	= ntohl(b[3]);
385 		r->clock_seq_low		= ntohl(b[4]);
386 
387 		for (loop = 0; loop < 6; loop++)
388 			r->node[loop] = ntohl(b[loop + 5]);
389 
390 		call->offset = 0;
391 		call->unmarshall++;
392 
393 	case 2:
394 		break;
395 	}
396 
397 	/* no unmarshalling required */
398 	call->state = AFS_CALL_REPLYING;
399 
400 	/* we'll need the file server record as that tells us which set of
401 	 * vnodes to operate upon */
402 	server = afs_find_server(&srx);
403 	if (!server)
404 		return -ENOTCONN;
405 	call->server = server;
406 
407 	INIT_WORK(&call->work, SRXAFSCB_InitCallBackState);
408 	queue_work(afs_wq, &call->work);
409 	return 0;
410 }
411 
412 /*
413  * allow the fileserver to see if the cache manager is still alive
414  */
415 static void SRXAFSCB_Probe(struct work_struct *work)
416 {
417 	struct afs_call *call = container_of(work, struct afs_call, work);
418 
419 	_enter("");
420 	afs_send_empty_reply(call);
421 	_leave("");
422 }
423 
424 /*
425  * deliver request data to a CB.Probe call
426  */
427 static int afs_deliver_cb_probe(struct afs_call *call)
428 {
429 	int ret;
430 
431 	_enter("");
432 
433 	ret = afs_extract_data(call, NULL, 0, false);
434 	if (ret < 0)
435 		return ret;
436 
437 	/* no unmarshalling required */
438 	call->state = AFS_CALL_REPLYING;
439 
440 	INIT_WORK(&call->work, SRXAFSCB_Probe);
441 	queue_work(afs_wq, &call->work);
442 	return 0;
443 }
444 
445 /*
446  * allow the fileserver to quickly find out if the fileserver has been rebooted
447  */
448 static void SRXAFSCB_ProbeUuid(struct work_struct *work)
449 {
450 	struct afs_call *call = container_of(work, struct afs_call, work);
451 	struct afs_uuid *r = call->request;
452 
453 	struct {
454 		__be32	match;
455 	} reply;
456 
457 	_enter("");
458 
459 	if (memcmp(r, &afs_uuid, sizeof(afs_uuid)) == 0)
460 		reply.match = htonl(0);
461 	else
462 		reply.match = htonl(1);
463 
464 	afs_send_simple_reply(call, &reply, sizeof(reply));
465 	_leave("");
466 }
467 
468 /*
469  * deliver request data to a CB.ProbeUuid call
470  */
471 static int afs_deliver_cb_probe_uuid(struct afs_call *call)
472 {
473 	struct afs_uuid *r;
474 	unsigned loop;
475 	__be32 *b;
476 	int ret;
477 
478 	_enter("{%u}", call->unmarshall);
479 
480 	switch (call->unmarshall) {
481 	case 0:
482 		call->offset = 0;
483 		call->buffer = kmalloc(11 * sizeof(__be32), GFP_KERNEL);
484 		if (!call->buffer)
485 			return -ENOMEM;
486 		call->unmarshall++;
487 
488 	case 1:
489 		_debug("extract UUID");
490 		ret = afs_extract_data(call, call->buffer,
491 				       11 * sizeof(__be32), false);
492 		switch (ret) {
493 		case 0:		break;
494 		case -EAGAIN:	return 0;
495 		default:	return ret;
496 		}
497 
498 		_debug("unmarshall UUID");
499 		call->request = kmalloc(sizeof(struct afs_uuid), GFP_KERNEL);
500 		if (!call->request)
501 			return -ENOMEM;
502 
503 		b = call->buffer;
504 		r = call->request;
505 		r->time_low			= ntohl(b[0]);
506 		r->time_mid			= ntohl(b[1]);
507 		r->time_hi_and_version		= ntohl(b[2]);
508 		r->clock_seq_hi_and_reserved 	= ntohl(b[3]);
509 		r->clock_seq_low		= ntohl(b[4]);
510 
511 		for (loop = 0; loop < 6; loop++)
512 			r->node[loop] = ntohl(b[loop + 5]);
513 
514 		call->offset = 0;
515 		call->unmarshall++;
516 
517 	case 2:
518 		break;
519 	}
520 
521 	call->state = AFS_CALL_REPLYING;
522 
523 	INIT_WORK(&call->work, SRXAFSCB_ProbeUuid);
524 	queue_work(afs_wq, &call->work);
525 	return 0;
526 }
527 
528 /*
529  * allow the fileserver to ask about the cache manager's capabilities
530  */
531 static void SRXAFSCB_TellMeAboutYourself(struct work_struct *work)
532 {
533 	struct afs_interface *ifs;
534 	struct afs_call *call = container_of(work, struct afs_call, work);
535 	int loop, nifs;
536 
537 	struct {
538 		struct /* InterfaceAddr */ {
539 			__be32 nifs;
540 			__be32 uuid[11];
541 			__be32 ifaddr[32];
542 			__be32 netmask[32];
543 			__be32 mtu[32];
544 		} ia;
545 		struct /* Capabilities */ {
546 			__be32 capcount;
547 			__be32 caps[1];
548 		} cap;
549 	} reply;
550 
551 	_enter("");
552 
553 	nifs = 0;
554 	ifs = kcalloc(32, sizeof(*ifs), GFP_KERNEL);
555 	if (ifs) {
556 		nifs = afs_get_ipv4_interfaces(ifs, 32, false);
557 		if (nifs < 0) {
558 			kfree(ifs);
559 			ifs = NULL;
560 			nifs = 0;
561 		}
562 	}
563 
564 	memset(&reply, 0, sizeof(reply));
565 	reply.ia.nifs = htonl(nifs);
566 
567 	reply.ia.uuid[0] = htonl(afs_uuid.time_low);
568 	reply.ia.uuid[1] = htonl(afs_uuid.time_mid);
569 	reply.ia.uuid[2] = htonl(afs_uuid.time_hi_and_version);
570 	reply.ia.uuid[3] = htonl((s8) afs_uuid.clock_seq_hi_and_reserved);
571 	reply.ia.uuid[4] = htonl((s8) afs_uuid.clock_seq_low);
572 	for (loop = 0; loop < 6; loop++)
573 		reply.ia.uuid[loop + 5] = htonl((s8) afs_uuid.node[loop]);
574 
575 	if (ifs) {
576 		for (loop = 0; loop < nifs; loop++) {
577 			reply.ia.ifaddr[loop] = ifs[loop].address.s_addr;
578 			reply.ia.netmask[loop] = ifs[loop].netmask.s_addr;
579 			reply.ia.mtu[loop] = htonl(ifs[loop].mtu);
580 		}
581 		kfree(ifs);
582 	}
583 
584 	reply.cap.capcount = htonl(1);
585 	reply.cap.caps[0] = htonl(AFS_CAP_ERROR_TRANSLATION);
586 	afs_send_simple_reply(call, &reply, sizeof(reply));
587 
588 	_leave("");
589 }
590 
591 /*
592  * deliver request data to a CB.TellMeAboutYourself call
593  */
594 static int afs_deliver_cb_tell_me_about_yourself(struct afs_call *call)
595 {
596 	int ret;
597 
598 	_enter("");
599 
600 	ret = afs_extract_data(call, NULL, 0, false);
601 	if (ret < 0)
602 		return ret;
603 
604 	/* no unmarshalling required */
605 	call->state = AFS_CALL_REPLYING;
606 
607 	INIT_WORK(&call->work, SRXAFSCB_TellMeAboutYourself);
608 	queue_work(afs_wq, &call->work);
609 	return 0;
610 }
611