xref: /linux/drivers/hv/channel_mgmt.c (revision 068df0f34e81bc06c5eb5012ec2eda25624e87aa)
1 /*
2  * Copyright (c) 2009, Microsoft Corporation.
3  *
4  * This program is free software; you can redistribute it and/or modify it
5  * under the terms and conditions of the GNU General Public License,
6  * version 2, as published by the Free Software Foundation.
7  *
8  * This program is distributed in the hope it will be useful, but WITHOUT
9  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
10  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
11  * more details.
12  *
13  * You should have received a copy of the GNU General Public License along with
14  * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
15  * Place - Suite 330, Boston, MA 02111-1307 USA.
16  *
17  * Authors:
18  *   Haiyang Zhang <haiyangz@microsoft.com>
19  *   Hank Janssen  <hjanssen@microsoft.com>
20  */
21 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
22 
23 #include <linux/kernel.h>
24 #include <linux/sched.h>
25 #include <linux/wait.h>
26 #include <linux/mm.h>
27 #include <linux/slab.h>
28 #include <linux/list.h>
29 #include <linux/module.h>
30 #include <linux/completion.h>
31 #include <linux/hyperv.h>
32 
33 #include "hyperv_vmbus.h"
34 
35 struct vmbus_channel_message_table_entry {
36 	enum vmbus_channel_message_type message_type;
37 	void (*message_handler)(struct vmbus_channel_message_header *msg);
38 };
39 
40 #define MAX_MSG_TYPES                    4
41 #define MAX_NUM_DEVICE_CLASSES_SUPPORTED 8
42 
43 static const uuid_le
44 	supported_device_classes[MAX_NUM_DEVICE_CLASSES_SUPPORTED] = {
45 	/* {ba6163d9-04a1-4d29-b605-72e2ffb1dc7f} */
46 	/* Storage - SCSI */
47 	{
48 		.b  = {
49 			0xd9, 0x63, 0x61, 0xba, 0xa1, 0x04, 0x29, 0x4d,
50 			0xb6, 0x05, 0x72, 0xe2, 0xff, 0xb1, 0xdc, 0x7f
51 		}
52 	},
53 
54 	/* {F8615163-DF3E-46c5-913F-F2D2F965ED0E} */
55 	/* Network */
56 	{
57 		.b = {
58 			0x63, 0x51, 0x61, 0xF8, 0x3E, 0xDF, 0xc5, 0x46,
59 			0x91, 0x3F, 0xF2, 0xD2, 0xF9, 0x65, 0xED, 0x0E
60 		}
61 	},
62 
63 	/* {CFA8B69E-5B4A-4cc0-B98B-8BA1A1F3F95A} */
64 	/* Input */
65 	{
66 		.b = {
67 			0x9E, 0xB6, 0xA8, 0xCF, 0x4A, 0x5B, 0xc0, 0x4c,
68 			0xB9, 0x8B, 0x8B, 0xA1, 0xA1, 0xF3, 0xF9, 0x5A
69 		}
70 	},
71 
72 	/* {32412632-86cb-44a2-9b5c-50d1417354f5} */
73 	/* IDE */
74 	{
75 		.b = {
76 			0x32, 0x26, 0x41, 0x32, 0xcb, 0x86, 0xa2, 0x44,
77 			0x9b, 0x5c, 0x50, 0xd1, 0x41, 0x73, 0x54, 0xf5
78 		}
79 	},
80 	/* 0E0B6031-5213-4934-818B-38D90CED39DB */
81 	/* Shutdown */
82 	{
83 		.b = {
84 			0x31, 0x60, 0x0B, 0X0E, 0x13, 0x52, 0x34, 0x49,
85 			0x81, 0x8B, 0x38, 0XD9, 0x0C, 0xED, 0x39, 0xDB
86 		}
87 	},
88 	/* {9527E630-D0AE-497b-ADCE-E80AB0175CAF} */
89 	/* TimeSync */
90 	{
91 		.b = {
92 			0x30, 0xe6, 0x27, 0x95, 0xae, 0xd0, 0x7b, 0x49,
93 			0xad, 0xce, 0xe8, 0x0a, 0xb0, 0x17, 0x5c, 0xaf
94 		}
95 	},
96 	/* {57164f39-9115-4e78-ab55-382f3bd5422d} */
97 	/* Heartbeat */
98 	{
99 		.b = {
100 			0x39, 0x4f, 0x16, 0x57, 0x15, 0x91, 0x78, 0x4e,
101 			0xab, 0x55, 0x38, 0x2f, 0x3b, 0xd5, 0x42, 0x2d
102 		}
103 	},
104 	/* {A9A0F4E7-5A45-4d96-B827-8A841E8C03E6} */
105 	/* KVP */
106 	{
107 		.b = {
108 			0xe7, 0xf4, 0xa0, 0xa9, 0x45, 0x5a, 0x96, 0x4d,
109 			0xb8, 0x27, 0x8a, 0x84, 0x1e, 0x8c, 0x3,  0xe6
110 	}
111 	},
112 
113 };
114 
115 
116 /**
117  * vmbus_prep_negotiate_resp() - Create default response for Hyper-V Negotiate message
118  * @icmsghdrp: Pointer to msg header structure
119  * @icmsg_negotiate: Pointer to negotiate message structure
120  * @buf: Raw buffer channel data
121  *
122  * @icmsghdrp is of type &struct icmsg_hdr.
123  * @negop is of type &struct icmsg_negotiate.
124  * Set up and fill in default negotiate response message. This response can
125  * come from both the vmbus driver and the hv_utils driver. The current api
126  * will respond properly to both Windows 2008 and Windows 2008-R2 operating
127  * systems.
128  *
129  * Mainly used by Hyper-V drivers.
130  */
131 void vmbus_prep_negotiate_resp(struct icmsg_hdr *icmsghdrp,
132 			       struct icmsg_negotiate *negop, u8 *buf)
133 {
134 	if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) {
135 		icmsghdrp->icmsgsize = 0x10;
136 
137 		negop = (struct icmsg_negotiate *)&buf[
138 			sizeof(struct vmbuspipe_hdr) +
139 			sizeof(struct icmsg_hdr)];
140 
141 		if (negop->icframe_vercnt == 2 &&
142 		   negop->icversion_data[1].major == 3) {
143 			negop->icversion_data[0].major = 3;
144 			negop->icversion_data[0].minor = 0;
145 			negop->icversion_data[1].major = 3;
146 			negop->icversion_data[1].minor = 0;
147 		} else {
148 			negop->icversion_data[0].major = 1;
149 			negop->icversion_data[0].minor = 0;
150 			negop->icversion_data[1].major = 1;
151 			negop->icversion_data[1].minor = 0;
152 		}
153 
154 		negop->icframe_vercnt = 1;
155 		negop->icmsg_vercnt = 1;
156 	}
157 }
158 EXPORT_SYMBOL_GPL(vmbus_prep_negotiate_resp);
159 
160 /*
161  * alloc_channel - Allocate and initialize a vmbus channel object
162  */
163 static struct vmbus_channel *alloc_channel(void)
164 {
165 	struct vmbus_channel *channel;
166 
167 	channel = kzalloc(sizeof(*channel), GFP_ATOMIC);
168 	if (!channel)
169 		return NULL;
170 
171 	spin_lock_init(&channel->inbound_lock);
172 
173 	channel->controlwq = create_workqueue("hv_vmbus_ctl");
174 	if (!channel->controlwq) {
175 		kfree(channel);
176 		return NULL;
177 	}
178 
179 	return channel;
180 }
181 
182 /*
183  * release_hannel - Release the vmbus channel object itself
184  */
185 static void release_channel(struct work_struct *work)
186 {
187 	struct vmbus_channel *channel = container_of(work,
188 						     struct vmbus_channel,
189 						     work);
190 
191 	destroy_workqueue(channel->controlwq);
192 
193 	kfree(channel);
194 }
195 
196 /*
197  * free_channel - Release the resources used by the vmbus channel object
198  */
199 static void free_channel(struct vmbus_channel *channel)
200 {
201 
202 	/*
203 	 * We have to release the channel's workqueue/thread in the vmbus's
204 	 * workqueue/thread context
205 	 * ie we can't destroy ourselves.
206 	 */
207 	INIT_WORK(&channel->work, release_channel);
208 	queue_work(vmbus_connection.work_queue, &channel->work);
209 }
210 
211 
212 
213 /*
214  * vmbus_process_rescind_offer -
215  * Rescind the offer by initiating a device removal
216  */
217 static void vmbus_process_rescind_offer(struct work_struct *work)
218 {
219 	struct vmbus_channel *channel = container_of(work,
220 						     struct vmbus_channel,
221 						     work);
222 
223 	vmbus_device_unregister(channel->device_obj);
224 }
225 
226 /*
227  * vmbus_process_offer - Process the offer by creating a channel/device
228  * associated with this offer
229  */
230 static void vmbus_process_offer(struct work_struct *work)
231 {
232 	struct vmbus_channel *newchannel = container_of(work,
233 							struct vmbus_channel,
234 							work);
235 	struct vmbus_channel *channel;
236 	bool fnew = true;
237 	int ret;
238 	unsigned long flags;
239 
240 	/* The next possible work is rescind handling */
241 	INIT_WORK(&newchannel->work, vmbus_process_rescind_offer);
242 
243 	/* Make sure this is a new offer */
244 	spin_lock_irqsave(&vmbus_connection.channel_lock, flags);
245 
246 	list_for_each_entry(channel, &vmbus_connection.chn_list, listentry) {
247 		if (!uuid_le_cmp(channel->offermsg.offer.if_type,
248 			newchannel->offermsg.offer.if_type) &&
249 			!uuid_le_cmp(channel->offermsg.offer.if_instance,
250 				newchannel->offermsg.offer.if_instance)) {
251 			fnew = false;
252 			break;
253 		}
254 	}
255 
256 	if (fnew)
257 		list_add_tail(&newchannel->listentry,
258 			      &vmbus_connection.chn_list);
259 
260 	spin_unlock_irqrestore(&vmbus_connection.channel_lock, flags);
261 
262 	if (!fnew) {
263 		free_channel(newchannel);
264 		return;
265 	}
266 
267 	/*
268 	 * Start the process of binding this offer to the driver
269 	 * We need to set the DeviceObject field before calling
270 	 * vmbus_child_dev_add()
271 	 */
272 	newchannel->device_obj = vmbus_device_create(
273 		&newchannel->offermsg.offer.if_type,
274 		&newchannel->offermsg.offer.if_instance,
275 		newchannel);
276 
277 	/*
278 	 * Add the new device to the bus. This will kick off device-driver
279 	 * binding which eventually invokes the device driver's AddDevice()
280 	 * method.
281 	 */
282 	ret = vmbus_device_register(newchannel->device_obj);
283 	if (ret != 0) {
284 		pr_err("unable to add child device object (relid %d)\n",
285 			   newchannel->offermsg.child_relid);
286 
287 		spin_lock_irqsave(&vmbus_connection.channel_lock, flags);
288 		list_del(&newchannel->listentry);
289 		spin_unlock_irqrestore(&vmbus_connection.channel_lock, flags);
290 
291 		free_channel(newchannel);
292 	} else {
293 		/*
294 		 * This state is used to indicate a successful open
295 		 * so that when we do close the channel normally, we
296 		 * can cleanup properly
297 		 */
298 		newchannel->state = CHANNEL_OPEN_STATE;
299 	}
300 }
301 
302 /*
303  * vmbus_onoffer - Handler for channel offers from vmbus in parent partition.
304  *
305  */
306 static void vmbus_onoffer(struct vmbus_channel_message_header *hdr)
307 {
308 	struct vmbus_channel_offer_channel *offer;
309 	struct vmbus_channel *newchannel;
310 	uuid_le *guidtype;
311 	uuid_le *guidinstance;
312 	int i;
313 	int fsupported = 0;
314 
315 	offer = (struct vmbus_channel_offer_channel *)hdr;
316 	for (i = 0; i < MAX_NUM_DEVICE_CLASSES_SUPPORTED; i++) {
317 		if (!uuid_le_cmp(offer->offer.if_type,
318 				supported_device_classes[i])) {
319 			fsupported = 1;
320 			break;
321 		}
322 	}
323 
324 	if (!fsupported)
325 		return;
326 
327 	guidtype = &offer->offer.if_type;
328 	guidinstance = &offer->offer.if_instance;
329 
330 	/* Allocate the channel object and save this offer. */
331 	newchannel = alloc_channel();
332 	if (!newchannel) {
333 		pr_err("Unable to allocate channel object\n");
334 		return;
335 	}
336 
337 	memcpy(&newchannel->offermsg, offer,
338 	       sizeof(struct vmbus_channel_offer_channel));
339 	newchannel->monitor_grp = (u8)offer->monitorid / 32;
340 	newchannel->monitor_bit = (u8)offer->monitorid % 32;
341 
342 	INIT_WORK(&newchannel->work, vmbus_process_offer);
343 	queue_work(newchannel->controlwq, &newchannel->work);
344 }
345 
346 /*
347  * vmbus_onoffer_rescind - Rescind offer handler.
348  *
349  * We queue a work item to process this offer synchronously
350  */
351 static void vmbus_onoffer_rescind(struct vmbus_channel_message_header *hdr)
352 {
353 	struct vmbus_channel_rescind_offer *rescind;
354 	struct vmbus_channel *channel;
355 
356 	rescind = (struct vmbus_channel_rescind_offer *)hdr;
357 	channel = relid2channel(rescind->child_relid);
358 
359 	if (channel == NULL)
360 		/* Just return here, no channel found */
361 		return;
362 
363 	/* work is initialized for vmbus_process_rescind_offer() from
364 	 * vmbus_process_offer() where the channel got created */
365 	queue_work(channel->controlwq, &channel->work);
366 }
367 
368 /*
369  * vmbus_onoffers_delivered -
370  * This is invoked when all offers have been delivered.
371  *
372  * Nothing to do here.
373  */
374 static void vmbus_onoffers_delivered(
375 			struct vmbus_channel_message_header *hdr)
376 {
377 }
378 
379 /*
380  * vmbus_onopen_result - Open result handler.
381  *
382  * This is invoked when we received a response to our channel open request.
383  * Find the matching request, copy the response and signal the requesting
384  * thread.
385  */
386 static void vmbus_onopen_result(struct vmbus_channel_message_header *hdr)
387 {
388 	struct vmbus_channel_open_result *result;
389 	struct vmbus_channel_msginfo *msginfo;
390 	struct vmbus_channel_message_header *requestheader;
391 	struct vmbus_channel_open_channel *openmsg;
392 	unsigned long flags;
393 
394 	result = (struct vmbus_channel_open_result *)hdr;
395 
396 	/*
397 	 * Find the open msg, copy the result and signal/unblock the wait event
398 	 */
399 	spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
400 
401 	list_for_each_entry(msginfo, &vmbus_connection.chn_msg_list,
402 				msglistentry) {
403 		requestheader =
404 			(struct vmbus_channel_message_header *)msginfo->msg;
405 
406 		if (requestheader->msgtype == CHANNELMSG_OPENCHANNEL) {
407 			openmsg =
408 			(struct vmbus_channel_open_channel *)msginfo->msg;
409 			if (openmsg->child_relid == result->child_relid &&
410 			    openmsg->openid == result->openid) {
411 				memcpy(&msginfo->response.open_result,
412 				       result,
413 				       sizeof(
414 					struct vmbus_channel_open_result));
415 				complete(&msginfo->waitevent);
416 				break;
417 			}
418 		}
419 	}
420 	spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
421 }
422 
423 /*
424  * vmbus_ongpadl_created - GPADL created handler.
425  *
426  * This is invoked when we received a response to our gpadl create request.
427  * Find the matching request, copy the response and signal the requesting
428  * thread.
429  */
430 static void vmbus_ongpadl_created(struct vmbus_channel_message_header *hdr)
431 {
432 	struct vmbus_channel_gpadl_created *gpadlcreated;
433 	struct vmbus_channel_msginfo *msginfo;
434 	struct vmbus_channel_message_header *requestheader;
435 	struct vmbus_channel_gpadl_header *gpadlheader;
436 	unsigned long flags;
437 
438 	gpadlcreated = (struct vmbus_channel_gpadl_created *)hdr;
439 
440 	/*
441 	 * Find the establish msg, copy the result and signal/unblock the wait
442 	 * event
443 	 */
444 	spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
445 
446 	list_for_each_entry(msginfo, &vmbus_connection.chn_msg_list,
447 				msglistentry) {
448 		requestheader =
449 			(struct vmbus_channel_message_header *)msginfo->msg;
450 
451 		if (requestheader->msgtype == CHANNELMSG_GPADL_HEADER) {
452 			gpadlheader =
453 			(struct vmbus_channel_gpadl_header *)requestheader;
454 
455 			if ((gpadlcreated->child_relid ==
456 			     gpadlheader->child_relid) &&
457 			    (gpadlcreated->gpadl == gpadlheader->gpadl)) {
458 				memcpy(&msginfo->response.gpadl_created,
459 				       gpadlcreated,
460 				       sizeof(
461 					struct vmbus_channel_gpadl_created));
462 				complete(&msginfo->waitevent);
463 				break;
464 			}
465 		}
466 	}
467 	spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
468 }
469 
470 /*
471  * vmbus_ongpadl_torndown - GPADL torndown handler.
472  *
473  * This is invoked when we received a response to our gpadl teardown request.
474  * Find the matching request, copy the response and signal the requesting
475  * thread.
476  */
477 static void vmbus_ongpadl_torndown(
478 			struct vmbus_channel_message_header *hdr)
479 {
480 	struct vmbus_channel_gpadl_torndown *gpadl_torndown;
481 	struct vmbus_channel_msginfo *msginfo;
482 	struct vmbus_channel_message_header *requestheader;
483 	struct vmbus_channel_gpadl_teardown *gpadl_teardown;
484 	unsigned long flags;
485 
486 	gpadl_torndown = (struct vmbus_channel_gpadl_torndown *)hdr;
487 
488 	/*
489 	 * Find the open msg, copy the result and signal/unblock the wait event
490 	 */
491 	spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
492 
493 	list_for_each_entry(msginfo, &vmbus_connection.chn_msg_list,
494 				msglistentry) {
495 		requestheader =
496 			(struct vmbus_channel_message_header *)msginfo->msg;
497 
498 		if (requestheader->msgtype == CHANNELMSG_GPADL_TEARDOWN) {
499 			gpadl_teardown =
500 			(struct vmbus_channel_gpadl_teardown *)requestheader;
501 
502 			if (gpadl_torndown->gpadl == gpadl_teardown->gpadl) {
503 				memcpy(&msginfo->response.gpadl_torndown,
504 				       gpadl_torndown,
505 				       sizeof(
506 					struct vmbus_channel_gpadl_torndown));
507 				complete(&msginfo->waitevent);
508 				break;
509 			}
510 		}
511 	}
512 	spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
513 }
514 
515 /*
516  * vmbus_onversion_response - Version response handler
517  *
518  * This is invoked when we received a response to our initiate contact request.
519  * Find the matching request, copy the response and signal the requesting
520  * thread.
521  */
522 static void vmbus_onversion_response(
523 		struct vmbus_channel_message_header *hdr)
524 {
525 	struct vmbus_channel_msginfo *msginfo;
526 	struct vmbus_channel_message_header *requestheader;
527 	struct vmbus_channel_initiate_contact *initiate;
528 	struct vmbus_channel_version_response *version_response;
529 	unsigned long flags;
530 
531 	version_response = (struct vmbus_channel_version_response *)hdr;
532 	spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
533 
534 	list_for_each_entry(msginfo, &vmbus_connection.chn_msg_list,
535 				msglistentry) {
536 		requestheader =
537 			(struct vmbus_channel_message_header *)msginfo->msg;
538 
539 		if (requestheader->msgtype ==
540 		    CHANNELMSG_INITIATE_CONTACT) {
541 			initiate =
542 			(struct vmbus_channel_initiate_contact *)requestheader;
543 			memcpy(&msginfo->response.version_response,
544 			      version_response,
545 			      sizeof(struct vmbus_channel_version_response));
546 			complete(&msginfo->waitevent);
547 		}
548 	}
549 	spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
550 }
551 
552 /* Channel message dispatch table */
553 static struct vmbus_channel_message_table_entry
554 	channel_message_table[CHANNELMSG_COUNT] = {
555 	{CHANNELMSG_INVALID,			NULL},
556 	{CHANNELMSG_OFFERCHANNEL,		vmbus_onoffer},
557 	{CHANNELMSG_RESCIND_CHANNELOFFER,	vmbus_onoffer_rescind},
558 	{CHANNELMSG_REQUESTOFFERS,		NULL},
559 	{CHANNELMSG_ALLOFFERS_DELIVERED,	vmbus_onoffers_delivered},
560 	{CHANNELMSG_OPENCHANNEL,		NULL},
561 	{CHANNELMSG_OPENCHANNEL_RESULT,	vmbus_onopen_result},
562 	{CHANNELMSG_CLOSECHANNEL,		NULL},
563 	{CHANNELMSG_GPADL_HEADER,		NULL},
564 	{CHANNELMSG_GPADL_BODY,		NULL},
565 	{CHANNELMSG_GPADL_CREATED,		vmbus_ongpadl_created},
566 	{CHANNELMSG_GPADL_TEARDOWN,		NULL},
567 	{CHANNELMSG_GPADL_TORNDOWN,		vmbus_ongpadl_torndown},
568 	{CHANNELMSG_RELID_RELEASED,		NULL},
569 	{CHANNELMSG_INITIATE_CONTACT,		NULL},
570 	{CHANNELMSG_VERSION_RESPONSE,		vmbus_onversion_response},
571 	{CHANNELMSG_UNLOAD,			NULL},
572 };
573 
574 /*
575  * vmbus_onmessage - Handler for channel protocol messages.
576  *
577  * This is invoked in the vmbus worker thread context.
578  */
579 void vmbus_onmessage(void *context)
580 {
581 	struct hv_message *msg = context;
582 	struct vmbus_channel_message_header *hdr;
583 	int size;
584 
585 	hdr = (struct vmbus_channel_message_header *)msg->u.payload;
586 	size = msg->header.payload_size;
587 
588 	if (hdr->msgtype >= CHANNELMSG_COUNT) {
589 		pr_err("Received invalid channel message type %d size %d\n",
590 			   hdr->msgtype, size);
591 		print_hex_dump_bytes("", DUMP_PREFIX_NONE,
592 				     (unsigned char *)msg->u.payload, size);
593 		return;
594 	}
595 
596 	if (channel_message_table[hdr->msgtype].message_handler)
597 		channel_message_table[hdr->msgtype].message_handler(hdr);
598 	else
599 		pr_err("Unhandled channel message type %d\n", hdr->msgtype);
600 }
601 
602 /*
603  * vmbus_request_offers - Send a request to get all our pending offers.
604  */
605 int vmbus_request_offers(void)
606 {
607 	struct vmbus_channel_message_header *msg;
608 	struct vmbus_channel_msginfo *msginfo;
609 	int ret, t;
610 
611 	msginfo = kmalloc(sizeof(*msginfo) +
612 			  sizeof(struct vmbus_channel_message_header),
613 			  GFP_KERNEL);
614 	if (!msginfo)
615 		return -ENOMEM;
616 
617 	init_completion(&msginfo->waitevent);
618 
619 	msg = (struct vmbus_channel_message_header *)msginfo->msg;
620 
621 	msg->msgtype = CHANNELMSG_REQUESTOFFERS;
622 
623 
624 	ret = vmbus_post_msg(msg,
625 			       sizeof(struct vmbus_channel_message_header));
626 	if (ret != 0) {
627 		pr_err("Unable to request offers - %d\n", ret);
628 
629 		goto cleanup;
630 	}
631 
632 	t = wait_for_completion_timeout(&msginfo->waitevent, 5*HZ);
633 	if (t == 0) {
634 		ret = -ETIMEDOUT;
635 		goto cleanup;
636 	}
637 
638 
639 
640 cleanup:
641 	kfree(msginfo);
642 
643 	return ret;
644 }
645 
646 /* eof */
647