xref: /openbmc/linux/fs/afs/cmservice.c (revision 827634ad)
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 #if 0
21 struct workqueue_struct *afs_cm_workqueue;
22 #endif  /*  0  */
23 
24 static int afs_deliver_cb_init_call_back_state(struct afs_call *,
25 					       struct sk_buff *, bool);
26 static int afs_deliver_cb_init_call_back_state3(struct afs_call *,
27 						struct sk_buff *, bool);
28 static int afs_deliver_cb_probe(struct afs_call *, struct sk_buff *, bool);
29 static int afs_deliver_cb_callback(struct afs_call *, struct sk_buff *, bool);
30 static int afs_deliver_cb_probe_uuid(struct afs_call *, struct sk_buff *, bool);
31 static int afs_deliver_cb_tell_me_about_yourself(struct afs_call *,
32 						 struct sk_buff *, bool);
33 static void afs_cm_destructor(struct afs_call *);
34 
35 /*
36  * CB.CallBack operation type
37  */
38 static const struct afs_call_type afs_SRXCBCallBack = {
39 	.name		= "CB.CallBack",
40 	.deliver	= afs_deliver_cb_callback,
41 	.abort_to_error	= afs_abort_to_error,
42 	.destructor	= afs_cm_destructor,
43 };
44 
45 /*
46  * CB.InitCallBackState operation type
47  */
48 static const struct afs_call_type afs_SRXCBInitCallBackState = {
49 	.name		= "CB.InitCallBackState",
50 	.deliver	= afs_deliver_cb_init_call_back_state,
51 	.abort_to_error	= afs_abort_to_error,
52 	.destructor	= afs_cm_destructor,
53 };
54 
55 /*
56  * CB.InitCallBackState3 operation type
57  */
58 static const struct afs_call_type afs_SRXCBInitCallBackState3 = {
59 	.name		= "CB.InitCallBackState3",
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 const struct afs_call_type afs_SRXCBProbe = {
69 	.name		= "CB.Probe",
70 	.deliver	= afs_deliver_cb_probe,
71 	.abort_to_error	= afs_abort_to_error,
72 	.destructor	= afs_cm_destructor,
73 };
74 
75 /*
76  * CB.ProbeUuid operation type
77  */
78 static const struct afs_call_type afs_SRXCBProbeUuid = {
79 	.name		= "CB.ProbeUuid",
80 	.deliver	= afs_deliver_cb_probe_uuid,
81 	.abort_to_error	= afs_abort_to_error,
82 	.destructor	= afs_cm_destructor,
83 };
84 
85 /*
86  * CB.TellMeAboutYourself operation type
87  */
88 static const struct afs_call_type afs_SRXCBTellMeAboutYourself = {
89 	.name		= "CB.TellMeAboutYourself",
90 	.deliver	= afs_deliver_cb_tell_me_about_yourself,
91 	.abort_to_error	= afs_abort_to_error,
92 	.destructor	= afs_cm_destructor,
93 };
94 
95 /*
96  * route an incoming cache manager call
97  * - return T if supported, F if not
98  */
99 bool afs_cm_incoming_call(struct afs_call *call)
100 {
101 	u32 operation_id = ntohl(call->operation_ID);
102 
103 	_enter("{CB.OP %u}", operation_id);
104 
105 	switch (operation_id) {
106 	case CBCallBack:
107 		call->type = &afs_SRXCBCallBack;
108 		return true;
109 	case CBInitCallBackState:
110 		call->type = &afs_SRXCBInitCallBackState;
111 		return true;
112 	case CBInitCallBackState3:
113 		call->type = &afs_SRXCBInitCallBackState3;
114 		return true;
115 	case CBProbe:
116 		call->type = &afs_SRXCBProbe;
117 		return true;
118 	case CBTellMeAboutYourself:
119 		call->type = &afs_SRXCBTellMeAboutYourself;
120 		return true;
121 	default:
122 		return false;
123 	}
124 }
125 
126 /*
127  * clean up a cache manager call
128  */
129 static void afs_cm_destructor(struct afs_call *call)
130 {
131 	_enter("");
132 
133 	/* Break the callbacks here so that we do it after the final ACK is
134 	 * received.  The step number here must match the final number in
135 	 * afs_deliver_cb_callback().
136 	 */
137 	if (call->unmarshall == 6) {
138 		ASSERT(call->server && call->count && call->request);
139 		afs_break_callbacks(call->server, call->count, call->request);
140 	}
141 
142 	afs_put_server(call->server);
143 	call->server = NULL;
144 	kfree(call->buffer);
145 	call->buffer = NULL;
146 }
147 
148 /*
149  * allow the fileserver to see if the cache manager is still alive
150  */
151 static void SRXAFSCB_CallBack(struct work_struct *work)
152 {
153 	struct afs_call *call = container_of(work, struct afs_call, work);
154 
155 	_enter("");
156 
157 	/* be sure to send the reply *before* attempting to spam the AFS server
158 	 * with FSFetchStatus requests on the vnodes with broken callbacks lest
159 	 * the AFS server get into a vicious cycle of trying to break further
160 	 * callbacks because it hadn't received completion of the CBCallBack op
161 	 * yet */
162 	afs_send_empty_reply(call);
163 
164 	afs_break_callbacks(call->server, call->count, call->request);
165 	_leave("");
166 }
167 
168 /*
169  * deliver request data to a CB.CallBack call
170  */
171 static int afs_deliver_cb_callback(struct afs_call *call, struct sk_buff *skb,
172 				   bool last)
173 {
174 	struct afs_callback *cb;
175 	struct afs_server *server;
176 	struct in_addr addr;
177 	__be32 *bp;
178 	u32 tmp;
179 	int ret, loop;
180 
181 	_enter("{%u},{%u},%d", call->unmarshall, skb->len, last);
182 
183 	switch (call->unmarshall) {
184 	case 0:
185 		call->offset = 0;
186 		call->unmarshall++;
187 
188 		/* extract the FID array and its count in two steps */
189 	case 1:
190 		_debug("extract FID count");
191 		ret = afs_extract_data(call, skb, last, &call->tmp, 4);
192 		switch (ret) {
193 		case 0:		break;
194 		case -EAGAIN:	return 0;
195 		default:	return ret;
196 		}
197 
198 		call->count = ntohl(call->tmp);
199 		_debug("FID count: %u", call->count);
200 		if (call->count > AFSCBMAX)
201 			return -EBADMSG;
202 
203 		call->buffer = kmalloc(call->count * 3 * 4, GFP_KERNEL);
204 		if (!call->buffer)
205 			return -ENOMEM;
206 		call->offset = 0;
207 		call->unmarshall++;
208 
209 	case 2:
210 		_debug("extract FID array");
211 		ret = afs_extract_data(call, skb, last, call->buffer,
212 				       call->count * 3 * 4);
213 		switch (ret) {
214 		case 0:		break;
215 		case -EAGAIN:	return 0;
216 		default:	return ret;
217 		}
218 
219 		_debug("unmarshall FID array");
220 		call->request = kcalloc(call->count,
221 					sizeof(struct afs_callback),
222 					GFP_KERNEL);
223 		if (!call->request)
224 			return -ENOMEM;
225 
226 		cb = call->request;
227 		bp = call->buffer;
228 		for (loop = call->count; loop > 0; loop--, cb++) {
229 			cb->fid.vid	= ntohl(*bp++);
230 			cb->fid.vnode	= ntohl(*bp++);
231 			cb->fid.unique	= ntohl(*bp++);
232 			cb->type	= AFSCM_CB_UNTYPED;
233 		}
234 
235 		call->offset = 0;
236 		call->unmarshall++;
237 
238 		/* extract the callback array and its count in two steps */
239 	case 3:
240 		_debug("extract CB count");
241 		ret = afs_extract_data(call, skb, last, &call->tmp, 4);
242 		switch (ret) {
243 		case 0:		break;
244 		case -EAGAIN:	return 0;
245 		default:	return ret;
246 		}
247 
248 		tmp = ntohl(call->tmp);
249 		_debug("CB count: %u", tmp);
250 		if (tmp != call->count && tmp != 0)
251 			return -EBADMSG;
252 		call->offset = 0;
253 		call->unmarshall++;
254 		if (tmp == 0)
255 			goto empty_cb_array;
256 
257 	case 4:
258 		_debug("extract CB array");
259 		ret = afs_extract_data(call, skb, last, call->request,
260 				       call->count * 3 * 4);
261 		switch (ret) {
262 		case 0:		break;
263 		case -EAGAIN:	return 0;
264 		default:	return ret;
265 		}
266 
267 		_debug("unmarshall CB array");
268 		cb = call->request;
269 		bp = call->buffer;
270 		for (loop = call->count; loop > 0; loop--, cb++) {
271 			cb->version	= ntohl(*bp++);
272 			cb->expiry	= ntohl(*bp++);
273 			cb->type	= ntohl(*bp++);
274 		}
275 
276 	empty_cb_array:
277 		call->offset = 0;
278 		call->unmarshall++;
279 
280 	case 5:
281 		_debug("trailer");
282 		if (skb->len != 0)
283 			return -EBADMSG;
284 
285 		/* Record that the message was unmarshalled successfully so
286 		 * that the call destructor can know do the callback breaking
287 		 * work, even if the final ACK isn't received.
288 		 *
289 		 * If the step number changes, then afs_cm_destructor() must be
290 		 * updated also.
291 		 */
292 		call->unmarshall++;
293 	case 6:
294 		break;
295 	}
296 
297 	if (!last)
298 		return 0;
299 
300 	call->state = AFS_CALL_REPLYING;
301 
302 	/* we'll need the file server record as that tells us which set of
303 	 * vnodes to operate upon */
304 	memcpy(&addr, &ip_hdr(skb)->saddr, 4);
305 	server = afs_find_server(&addr);
306 	if (!server)
307 		return -ENOTCONN;
308 	call->server = server;
309 
310 	INIT_WORK(&call->work, SRXAFSCB_CallBack);
311 	queue_work(afs_wq, &call->work);
312 	return 0;
313 }
314 
315 /*
316  * allow the fileserver to request callback state (re-)initialisation
317  */
318 static void SRXAFSCB_InitCallBackState(struct work_struct *work)
319 {
320 	struct afs_call *call = container_of(work, struct afs_call, work);
321 
322 	_enter("{%p}", call->server);
323 
324 	afs_init_callback_state(call->server);
325 	afs_send_empty_reply(call);
326 	_leave("");
327 }
328 
329 /*
330  * deliver request data to a CB.InitCallBackState call
331  */
332 static int afs_deliver_cb_init_call_back_state(struct afs_call *call,
333 					       struct sk_buff *skb,
334 					       bool last)
335 {
336 	struct afs_server *server;
337 	struct in_addr addr;
338 
339 	_enter(",{%u},%d", skb->len, last);
340 
341 	if (skb->len > 0)
342 		return -EBADMSG;
343 	if (!last)
344 		return 0;
345 
346 	/* no unmarshalling required */
347 	call->state = AFS_CALL_REPLYING;
348 
349 	/* we'll need the file server record as that tells us which set of
350 	 * vnodes to operate upon */
351 	memcpy(&addr, &ip_hdr(skb)->saddr, 4);
352 	server = afs_find_server(&addr);
353 	if (!server)
354 		return -ENOTCONN;
355 	call->server = server;
356 
357 	INIT_WORK(&call->work, SRXAFSCB_InitCallBackState);
358 	queue_work(afs_wq, &call->work);
359 	return 0;
360 }
361 
362 /*
363  * deliver request data to a CB.InitCallBackState3 call
364  */
365 static int afs_deliver_cb_init_call_back_state3(struct afs_call *call,
366 						struct sk_buff *skb,
367 						bool last)
368 {
369 	struct afs_server *server;
370 	struct in_addr addr;
371 
372 	_enter(",{%u},%d", skb->len, last);
373 
374 	if (!last)
375 		return 0;
376 
377 	/* no unmarshalling required */
378 	call->state = AFS_CALL_REPLYING;
379 
380 	/* we'll need the file server record as that tells us which set of
381 	 * vnodes to operate upon */
382 	memcpy(&addr, &ip_hdr(skb)->saddr, 4);
383 	server = afs_find_server(&addr);
384 	if (!server)
385 		return -ENOTCONN;
386 	call->server = server;
387 
388 	INIT_WORK(&call->work, SRXAFSCB_InitCallBackState);
389 	queue_work(afs_wq, &call->work);
390 	return 0;
391 }
392 
393 /*
394  * allow the fileserver to see if the cache manager is still alive
395  */
396 static void SRXAFSCB_Probe(struct work_struct *work)
397 {
398 	struct afs_call *call = container_of(work, struct afs_call, work);
399 
400 	_enter("");
401 	afs_send_empty_reply(call);
402 	_leave("");
403 }
404 
405 /*
406  * deliver request data to a CB.Probe call
407  */
408 static int afs_deliver_cb_probe(struct afs_call *call, struct sk_buff *skb,
409 				bool last)
410 {
411 	_enter(",{%u},%d", skb->len, last);
412 
413 	if (skb->len > 0)
414 		return -EBADMSG;
415 	if (!last)
416 		return 0;
417 
418 	/* no unmarshalling required */
419 	call->state = AFS_CALL_REPLYING;
420 
421 	INIT_WORK(&call->work, SRXAFSCB_Probe);
422 	queue_work(afs_wq, &call->work);
423 	return 0;
424 }
425 
426 /*
427  * allow the fileserver to quickly find out if the fileserver has been rebooted
428  */
429 static void SRXAFSCB_ProbeUuid(struct work_struct *work)
430 {
431 	struct afs_call *call = container_of(work, struct afs_call, work);
432 	struct afs_uuid *r = call->request;
433 
434 	struct {
435 		__be32	match;
436 	} reply;
437 
438 	_enter("");
439 
440 
441 	if (memcmp(r, &afs_uuid, sizeof(afs_uuid)) == 0)
442 		reply.match = htonl(0);
443 	else
444 		reply.match = htonl(1);
445 
446 	afs_send_simple_reply(call, &reply, sizeof(reply));
447 	_leave("");
448 }
449 
450 /*
451  * deliver request data to a CB.ProbeUuid call
452  */
453 static int afs_deliver_cb_probe_uuid(struct afs_call *call, struct sk_buff *skb,
454 				     bool last)
455 {
456 	struct afs_uuid *r;
457 	unsigned loop;
458 	__be32 *b;
459 	int ret;
460 
461 	_enter("{%u},{%u},%d", call->unmarshall, skb->len, last);
462 
463 	if (skb->len > 0)
464 		return -EBADMSG;
465 	if (!last)
466 		return 0;
467 
468 	switch (call->unmarshall) {
469 	case 0:
470 		call->offset = 0;
471 		call->buffer = kmalloc(11 * sizeof(__be32), GFP_KERNEL);
472 		if (!call->buffer)
473 			return -ENOMEM;
474 		call->unmarshall++;
475 
476 	case 1:
477 		_debug("extract UUID");
478 		ret = afs_extract_data(call, skb, last, call->buffer,
479 				       11 * sizeof(__be32));
480 		switch (ret) {
481 		case 0:		break;
482 		case -EAGAIN:	return 0;
483 		default:	return ret;
484 		}
485 
486 		_debug("unmarshall UUID");
487 		call->request = kmalloc(sizeof(struct afs_uuid), GFP_KERNEL);
488 		if (!call->request)
489 			return -ENOMEM;
490 
491 		b = call->buffer;
492 		r = call->request;
493 		r->time_low			= ntohl(b[0]);
494 		r->time_mid			= ntohl(b[1]);
495 		r->time_hi_and_version		= ntohl(b[2]);
496 		r->clock_seq_hi_and_reserved 	= ntohl(b[3]);
497 		r->clock_seq_low		= ntohl(b[4]);
498 
499 		for (loop = 0; loop < 6; loop++)
500 			r->node[loop] = ntohl(b[loop + 5]);
501 
502 		call->offset = 0;
503 		call->unmarshall++;
504 
505 	case 2:
506 		_debug("trailer");
507 		if (skb->len != 0)
508 			return -EBADMSG;
509 		break;
510 	}
511 
512 	if (!last)
513 		return 0;
514 
515 	call->state = AFS_CALL_REPLYING;
516 
517 	INIT_WORK(&call->work, SRXAFSCB_ProbeUuid);
518 	queue_work(afs_wq, &call->work);
519 	return 0;
520 }
521 
522 /*
523  * allow the fileserver to ask about the cache manager's capabilities
524  */
525 static void SRXAFSCB_TellMeAboutYourself(struct work_struct *work)
526 {
527 	struct afs_interface *ifs;
528 	struct afs_call *call = container_of(work, struct afs_call, work);
529 	int loop, nifs;
530 
531 	struct {
532 		struct /* InterfaceAddr */ {
533 			__be32 nifs;
534 			__be32 uuid[11];
535 			__be32 ifaddr[32];
536 			__be32 netmask[32];
537 			__be32 mtu[32];
538 		} ia;
539 		struct /* Capabilities */ {
540 			__be32 capcount;
541 			__be32 caps[1];
542 		} cap;
543 	} reply;
544 
545 	_enter("");
546 
547 	nifs = 0;
548 	ifs = kcalloc(32, sizeof(*ifs), GFP_KERNEL);
549 	if (ifs) {
550 		nifs = afs_get_ipv4_interfaces(ifs, 32, false);
551 		if (nifs < 0) {
552 			kfree(ifs);
553 			ifs = NULL;
554 			nifs = 0;
555 		}
556 	}
557 
558 	memset(&reply, 0, sizeof(reply));
559 	reply.ia.nifs = htonl(nifs);
560 
561 	reply.ia.uuid[0] = htonl(afs_uuid.time_low);
562 	reply.ia.uuid[1] = htonl(afs_uuid.time_mid);
563 	reply.ia.uuid[2] = htonl(afs_uuid.time_hi_and_version);
564 	reply.ia.uuid[3] = htonl((s8) afs_uuid.clock_seq_hi_and_reserved);
565 	reply.ia.uuid[4] = htonl((s8) afs_uuid.clock_seq_low);
566 	for (loop = 0; loop < 6; loop++)
567 		reply.ia.uuid[loop + 5] = htonl((s8) afs_uuid.node[loop]);
568 
569 	if (ifs) {
570 		for (loop = 0; loop < nifs; loop++) {
571 			reply.ia.ifaddr[loop] = ifs[loop].address.s_addr;
572 			reply.ia.netmask[loop] = ifs[loop].netmask.s_addr;
573 			reply.ia.mtu[loop] = htonl(ifs[loop].mtu);
574 		}
575 		kfree(ifs);
576 	}
577 
578 	reply.cap.capcount = htonl(1);
579 	reply.cap.caps[0] = htonl(AFS_CAP_ERROR_TRANSLATION);
580 	afs_send_simple_reply(call, &reply, sizeof(reply));
581 
582 	_leave("");
583 }
584 
585 /*
586  * deliver request data to a CB.TellMeAboutYourself call
587  */
588 static int afs_deliver_cb_tell_me_about_yourself(struct afs_call *call,
589 						 struct sk_buff *skb, bool last)
590 {
591 	_enter(",{%u},%d", skb->len, last);
592 
593 	if (skb->len > 0)
594 		return -EBADMSG;
595 	if (!last)
596 		return 0;
597 
598 	/* no unmarshalling required */
599 	call->state = AFS_CALL_REPLYING;
600 
601 	INIT_WORK(&call->work, SRXAFSCB_TellMeAboutYourself);
602 	queue_work(afs_wq, &call->work);
603 	return 0;
604 }
605