xref: /freebsd/sys/dev/hyperv/utilities/hv_kvp.c (revision 0b3105a37d7adcadcb720112fed4dc4e8040be99)
1 /*-
2  * Copyright (c) 2014 Microsoft Corp.
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice unmodified, this list of conditions, and the following
10  *    disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25  */
26 
27 /*
28  *	Author:	Sainath Varanasi.
29  *	Date:	4/2012
30  *	Email:	bsdic@microsoft.com
31  */
32 
33 #include <sys/cdefs.h>
34 __FBSDID("$FreeBSD$");
35 
36 #include <sys/param.h>
37 #include <sys/kernel.h>
38 #include <sys/conf.h>
39 #include <sys/uio.h>
40 #include <sys/bus.h>
41 #include <sys/malloc.h>
42 #include <sys/mbuf.h>
43 #include <sys/module.h>
44 #include <sys/reboot.h>
45 #include <sys/lock.h>
46 #include <sys/taskqueue.h>
47 #include <sys/selinfo.h>
48 #include <sys/sysctl.h>
49 #include <sys/poll.h>
50 #include <sys/proc.h>
51 #include <sys/kthread.h>
52 #include <sys/syscallsubr.h>
53 #include <sys/sysproto.h>
54 #include <sys/un.h>
55 #include <sys/endian.h>
56 #include <sys/_null.h>
57 #include <sys/signal.h>
58 #include <sys/syslog.h>
59 #include <sys/systm.h>
60 #include <sys/mutex.h>
61 #include <net/if_arp.h>
62 
63 #include <dev/hyperv/include/hyperv.h>
64 #include <dev/hyperv/netvsc/hv_net_vsc.h>
65 
66 #include "hv_util.h"
67 #include "unicode.h"
68 #include "hv_kvp.h"
69 
70 /* hv_kvp defines */
71 #define BUFFERSIZE	sizeof(struct hv_kvp_msg)
72 #define KVP_SUCCESS	0
73 #define KVP_ERROR	1
74 #define kvp_hdr		hdr.kvp_hdr
75 
76 /* hv_kvp debug control */
77 static int hv_kvp_log = 0;
78 
79 #define	hv_kvp_log_error(...)	do {				\
80 	if (hv_kvp_log > 0)				\
81 		log(LOG_ERR, "hv_kvp: " __VA_ARGS__);	\
82 } while (0)
83 
84 #define	hv_kvp_log_info(...) do {				\
85 	if (hv_kvp_log > 1)				\
86 		log(LOG_INFO, "hv_kvp: " __VA_ARGS__);		\
87 } while (0)
88 
89 static hv_guid service_guid = { .data =
90 	{0xe7, 0xf4, 0xa0, 0xa9, 0x45, 0x5a, 0x96, 0x4d,
91 	0xb8, 0x27, 0x8a, 0x84, 0x1e, 0x8c, 0x3,  0xe6} };
92 
93 /* character device prototypes */
94 static d_open_t		hv_kvp_dev_open;
95 static d_close_t	hv_kvp_dev_close;
96 static d_read_t		hv_kvp_dev_daemon_read;
97 static d_write_t	hv_kvp_dev_daemon_write;
98 static d_poll_t		hv_kvp_dev_daemon_poll;
99 
100 /* hv_kvp character device structure */
101 static struct cdevsw hv_kvp_cdevsw =
102 {
103 	.d_version	= D_VERSION,
104 	.d_open		= hv_kvp_dev_open,
105 	.d_close	= hv_kvp_dev_close,
106 	.d_read		= hv_kvp_dev_daemon_read,
107 	.d_write	= hv_kvp_dev_daemon_write,
108 	.d_poll		= hv_kvp_dev_daemon_poll,
109 	.d_name		= "hv_kvp_dev",
110 };
111 
112 
113 /*
114  * Global state to track and synchronize multiple
115  * KVP transaction requests from the host.
116  */
117 typedef struct hv_kvp_sc {
118 	struct hv_util_sc	util_sc;
119 
120 	/* Unless specified the pending mutex should be
121 	 * used to alter the values of the following paramters:
122 	 * 1. req_in_progress
123 	 * 2. req_timed_out
124 	 */
125 	struct mtx		pending_mutex;
126 
127 	struct task		task;
128 
129 	/* To track if transaction is active or not */
130 	boolean_t		req_in_progress;
131 	/* Tracks if daemon did not reply back in time */
132 	boolean_t		req_timed_out;
133 	/* Tracks if daemon is serving a request currently */
134 	boolean_t		daemon_busy;
135 
136 	/* Length of host message */
137 	uint32_t		host_msg_len;
138 
139 	/* Host message id */
140 	uint64_t		host_msg_id;
141 
142 	/* Current kvp message from the host */
143 	struct hv_kvp_msg	*host_kvp_msg;
144 
145 	 /* Current kvp message for daemon */
146 	struct hv_kvp_msg	daemon_kvp_msg;
147 
148 	/* Rcv buffer for communicating with the host*/
149 	uint8_t			*rcv_buf;
150 
151 	/* Device semaphore to control communication */
152 	struct sema		dev_sema;
153 
154 	/* Indicates if daemon registered with driver */
155 	boolean_t		register_done;
156 
157 	/* Character device status */
158 	boolean_t		dev_accessed;
159 
160 	struct cdev *hv_kvp_dev;
161 
162 	struct proc *daemon_task;
163 
164 	struct selinfo hv_kvp_selinfo;
165 } hv_kvp_sc;
166 
167 /* hv_kvp prototypes */
168 static int	hv_kvp_req_in_progress(hv_kvp_sc *sc);
169 static void	hv_kvp_transaction_init(hv_kvp_sc *sc, uint32_t, uint64_t, uint8_t *);
170 static void	hv_kvp_send_msg_to_daemon(hv_kvp_sc *sc);
171 static void	hv_kvp_process_request(void *context, int pending);
172 
173 /*
174  * hv_kvp low level functions
175  */
176 
177 /*
178  * Check if kvp transaction is in progres
179  */
180 static int
181 hv_kvp_req_in_progress(hv_kvp_sc *sc)
182 {
183 
184 	return (sc->req_in_progress);
185 }
186 
187 
188 /*
189  * This routine is called whenever a message is received from the host
190  */
191 static void
192 hv_kvp_transaction_init(hv_kvp_sc *sc, uint32_t rcv_len,
193 			uint64_t request_id, uint8_t *rcv_buf)
194 {
195 
196 	/* Store all the relevant message details in the global structure */
197 	/* Do not need to use mutex for req_in_progress here */
198 	sc->req_in_progress = true;
199 	sc->host_msg_len = rcv_len;
200 	sc->host_msg_id = request_id;
201 	sc->rcv_buf = rcv_buf;
202 	sc->host_kvp_msg = (struct hv_kvp_msg *)&rcv_buf[
203 		sizeof(struct hv_vmbus_pipe_hdr) +
204 		sizeof(struct hv_vmbus_icmsg_hdr)];
205 }
206 
207 
208 /*
209  * hv_kvp - version neogtiation function
210  */
211 static void
212 hv_kvp_negotiate_version(struct hv_vmbus_icmsg_hdr *icmsghdrp,
213 			 struct hv_vmbus_icmsg_negotiate *negop,
214 			 uint8_t *buf)
215 {
216 	int icframe_vercnt;
217 	int icmsg_vercnt;
218 
219 	icmsghdrp->icmsgsize = 0x10;
220 
221 	negop = (struct hv_vmbus_icmsg_negotiate *)&buf[
222 		sizeof(struct hv_vmbus_pipe_hdr) +
223 		sizeof(struct hv_vmbus_icmsg_hdr)];
224 	icframe_vercnt = negop->icframe_vercnt;
225 	icmsg_vercnt = negop->icmsg_vercnt;
226 
227 	/*
228 	 * Select the framework version number we will support
229 	 */
230 	if ((icframe_vercnt >= 2) && (negop->icversion_data[1].major == 3)) {
231 		icframe_vercnt = 3;
232 		if (icmsg_vercnt > 2)
233 			icmsg_vercnt = 4;
234 		else
235 			icmsg_vercnt = 3;
236 	} else {
237 		icframe_vercnt = 1;
238 		icmsg_vercnt = 1;
239 	}
240 
241 	negop->icframe_vercnt = 1;
242 	negop->icmsg_vercnt = 1;
243 	negop->icversion_data[0].major = icframe_vercnt;
244 	negop->icversion_data[0].minor = 0;
245 	negop->icversion_data[1].major = icmsg_vercnt;
246 	negop->icversion_data[1].minor = 0;
247 }
248 
249 
250 /*
251  * Convert ip related info in umsg from utf8 to utf16 and store in hmsg
252  */
253 static int
254 hv_kvp_convert_utf8_ipinfo_to_utf16(struct hv_kvp_msg *umsg,
255 				    struct hv_kvp_ip_msg *host_ip_msg)
256 {
257 	int err_ip, err_subnet, err_gway, err_dns, err_adap;
258 	int UNUSED_FLAG = 1;
259 
260 	utf8_to_utf16((uint16_t *)host_ip_msg->kvp_ip_val.ip_addr,
261 	    MAX_IP_ADDR_SIZE,
262 	    (char *)umsg->body.kvp_ip_val.ip_addr,
263 	    strlen((char *)umsg->body.kvp_ip_val.ip_addr),
264 	    UNUSED_FLAG,
265 	    &err_ip);
266 	utf8_to_utf16((uint16_t *)host_ip_msg->kvp_ip_val.sub_net,
267 	    MAX_IP_ADDR_SIZE,
268 	    (char *)umsg->body.kvp_ip_val.sub_net,
269 	    strlen((char *)umsg->body.kvp_ip_val.sub_net),
270 	    UNUSED_FLAG,
271 	    &err_subnet);
272 	utf8_to_utf16((uint16_t *)host_ip_msg->kvp_ip_val.gate_way,
273 	    MAX_GATEWAY_SIZE,
274 	    (char *)umsg->body.kvp_ip_val.gate_way,
275 	    strlen((char *)umsg->body.kvp_ip_val.gate_way),
276 	    UNUSED_FLAG,
277 	    &err_gway);
278 	utf8_to_utf16((uint16_t *)host_ip_msg->kvp_ip_val.dns_addr,
279 	    MAX_IP_ADDR_SIZE,
280 	    (char *)umsg->body.kvp_ip_val.dns_addr,
281 	    strlen((char *)umsg->body.kvp_ip_val.dns_addr),
282 	    UNUSED_FLAG,
283 	    &err_dns);
284 	utf8_to_utf16((uint16_t *)host_ip_msg->kvp_ip_val.adapter_id,
285 	    MAX_IP_ADDR_SIZE,
286 	    (char *)umsg->body.kvp_ip_val.adapter_id,
287 	    strlen((char *)umsg->body.kvp_ip_val.adapter_id),
288 	    UNUSED_FLAG,
289 	    &err_adap);
290 
291 	host_ip_msg->kvp_ip_val.dhcp_enabled = umsg->body.kvp_ip_val.dhcp_enabled;
292 	host_ip_msg->kvp_ip_val.addr_family = umsg->body.kvp_ip_val.addr_family;
293 
294 	return (err_ip | err_subnet | err_gway | err_dns | err_adap);
295 }
296 
297 
298 /*
299  * Convert ip related info in hmsg from utf16 to utf8 and store in umsg
300  */
301 static int
302 hv_kvp_convert_utf16_ipinfo_to_utf8(struct hv_kvp_ip_msg *host_ip_msg,
303 				    struct hv_kvp_msg *umsg)
304 {
305 	int err_ip, err_subnet, err_gway, err_dns, err_adap;
306 	int UNUSED_FLAG = 1;
307 	int guid_index;
308 	struct hv_device *hv_dev;       /* GUID Data Structure */
309 	hn_softc_t *sc;                 /* hn softc structure  */
310 	char if_name[4];
311 	unsigned char guid_instance[40];
312 	char *guid_data = NULL;
313 	char buf[39];
314 
315 	struct guid_extract {
316 		char	a1[2];
317 		char	a2[2];
318 		char	a3[2];
319 		char	a4[2];
320 		char	b1[2];
321 		char	b2[2];
322 		char	c1[2];
323 		char	c2[2];
324 		char	d[4];
325 		char	e[12];
326 	};
327 
328 	struct guid_extract *id;
329 	device_t *devs;
330 	int devcnt;
331 
332 	/* IP Address */
333 	utf16_to_utf8((char *)umsg->body.kvp_ip_val.ip_addr,
334 	    MAX_IP_ADDR_SIZE,
335 	    (uint16_t *)host_ip_msg->kvp_ip_val.ip_addr,
336 	    MAX_IP_ADDR_SIZE,
337 	    UNUSED_FLAG,
338 	    &err_ip);
339 
340 	/* Adapter ID : GUID */
341 	utf16_to_utf8((char *)umsg->body.kvp_ip_val.adapter_id,
342 	    MAX_ADAPTER_ID_SIZE,
343 	    (uint16_t *)host_ip_msg->kvp_ip_val.adapter_id,
344 	    MAX_ADAPTER_ID_SIZE,
345 	    UNUSED_FLAG,
346 	    &err_adap);
347 
348 	if (devclass_get_devices(devclass_find("hn"), &devs, &devcnt) == 0) {
349 		for (devcnt = devcnt - 1; devcnt >= 0; devcnt--) {
350 			sc = device_get_softc(devs[devcnt]);
351 
352 			/* Trying to find GUID of Network Device */
353 			hv_dev = sc->hn_dev_obj;
354 
355 			for (guid_index = 0; guid_index < 16; guid_index++) {
356 				sprintf(&guid_instance[guid_index * 2], "%02x",
357 				    hv_dev->device_id.data[guid_index]);
358 			}
359 
360 			guid_data = (char *)guid_instance;
361 			id = (struct guid_extract *)guid_data;
362 			snprintf(buf, sizeof(buf), "{%.2s%.2s%.2s%.2s-%.2s%.2s-%.2s%.2s-%.4s-%s}",
363 			    id->a4, id->a3, id->a2, id->a1,
364 			    id->b2, id->b1, id->c2, id->c1, id->d, id->e);
365 			guid_data = NULL;
366 			sprintf(if_name, "%s%d", "hn", device_get_unit(devs[devcnt]));
367 
368 			if (strncmp(buf, (char *)umsg->body.kvp_ip_val.adapter_id, 39) == 0) {
369 				strcpy((char *)umsg->body.kvp_ip_val.adapter_id, if_name);
370 				break;
371 			}
372 		}
373 		free(devs, M_TEMP);
374 	}
375 
376 	/* Address Family , DHCP , SUBNET, Gateway, DNS */
377 	umsg->kvp_hdr.operation = host_ip_msg->operation;
378 	umsg->body.kvp_ip_val.addr_family = host_ip_msg->kvp_ip_val.addr_family;
379 	umsg->body.kvp_ip_val.dhcp_enabled = host_ip_msg->kvp_ip_val.dhcp_enabled;
380 	utf16_to_utf8((char *)umsg->body.kvp_ip_val.sub_net, MAX_IP_ADDR_SIZE,
381 	    (uint16_t *)host_ip_msg->kvp_ip_val.sub_net,
382 	    MAX_IP_ADDR_SIZE,
383 	    UNUSED_FLAG,
384 	    &err_subnet);
385 
386 	utf16_to_utf8((char *)umsg->body.kvp_ip_val.gate_way, MAX_GATEWAY_SIZE,
387 	    (uint16_t *)host_ip_msg->kvp_ip_val.gate_way,
388 	    MAX_GATEWAY_SIZE,
389 	    UNUSED_FLAG,
390 	    &err_gway);
391 
392 	utf16_to_utf8((char *)umsg->body.kvp_ip_val.dns_addr, MAX_IP_ADDR_SIZE,
393 	    (uint16_t *)host_ip_msg->kvp_ip_val.dns_addr,
394 	    MAX_IP_ADDR_SIZE,
395 	    UNUSED_FLAG,
396 	    &err_dns);
397 
398 	return (err_ip | err_subnet | err_gway | err_dns | err_adap);
399 }
400 
401 
402 /*
403  * Prepare a user kvp msg based on host kvp msg (utf16 to utf8)
404  * Ensure utf16_utf8 takes care of the additional string terminating char!!
405  */
406 static void
407 hv_kvp_convert_hostmsg_to_usermsg(struct hv_kvp_msg *hmsg, struct hv_kvp_msg *umsg)
408 {
409 	int utf_err = 0;
410 	uint32_t value_type;
411 	struct hv_kvp_ip_msg *host_ip_msg;
412 
413 	host_ip_msg = (struct hv_kvp_ip_msg*)hmsg;
414 	memset(umsg, 0, sizeof(struct hv_kvp_msg));
415 
416 	umsg->kvp_hdr.operation = hmsg->kvp_hdr.operation;
417 	umsg->kvp_hdr.pool = hmsg->kvp_hdr.pool;
418 
419 	switch (umsg->kvp_hdr.operation) {
420 	case HV_KVP_OP_SET_IP_INFO:
421 		hv_kvp_convert_utf16_ipinfo_to_utf8(host_ip_msg, umsg);
422 		break;
423 
424 	case HV_KVP_OP_GET_IP_INFO:
425 		utf16_to_utf8((char *)umsg->body.kvp_ip_val.adapter_id,
426 		    MAX_ADAPTER_ID_SIZE,
427 		    (uint16_t *)host_ip_msg->kvp_ip_val.adapter_id,
428 		    MAX_ADAPTER_ID_SIZE, 1, &utf_err);
429 
430 		umsg->body.kvp_ip_val.addr_family =
431 		    host_ip_msg->kvp_ip_val.addr_family;
432 		break;
433 
434 	case HV_KVP_OP_SET:
435 		value_type = hmsg->body.kvp_set.data.value_type;
436 
437 		switch (value_type) {
438 		case HV_REG_SZ:
439 			umsg->body.kvp_set.data.value_size =
440 			    utf16_to_utf8(
441 				(char *)umsg->body.kvp_set.data.msg_value.value,
442 				HV_KVP_EXCHANGE_MAX_VALUE_SIZE - 1,
443 				(uint16_t *)hmsg->body.kvp_set.data.msg_value.value,
444 				hmsg->body.kvp_set.data.value_size,
445 				1, &utf_err);
446 			/* utf8 encoding */
447 			umsg->body.kvp_set.data.value_size =
448 			    umsg->body.kvp_set.data.value_size / 2;
449 			break;
450 
451 		case HV_REG_U32:
452 			umsg->body.kvp_set.data.value_size =
453 			    sprintf(umsg->body.kvp_set.data.msg_value.value, "%d",
454 				hmsg->body.kvp_set.data.msg_value.value_u32) + 1;
455 			break;
456 
457 		case HV_REG_U64:
458 			umsg->body.kvp_set.data.value_size =
459 			    sprintf(umsg->body.kvp_set.data.msg_value.value, "%llu",
460 				(unsigned long long)
461 				hmsg->body.kvp_set.data.msg_value.value_u64) + 1;
462 			break;
463 		}
464 
465 		umsg->body.kvp_set.data.key_size =
466 		    utf16_to_utf8(
467 			umsg->body.kvp_set.data.key,
468 			HV_KVP_EXCHANGE_MAX_KEY_SIZE - 1,
469 			(uint16_t *)hmsg->body.kvp_set.data.key,
470 			hmsg->body.kvp_set.data.key_size,
471 			1, &utf_err);
472 
473 		/* utf8 encoding */
474 		umsg->body.kvp_set.data.key_size =
475 		    umsg->body.kvp_set.data.key_size / 2;
476 		break;
477 
478 	case HV_KVP_OP_GET:
479 		umsg->body.kvp_get.data.key_size =
480 		    utf16_to_utf8(umsg->body.kvp_get.data.key,
481 			HV_KVP_EXCHANGE_MAX_KEY_SIZE - 1,
482 			(uint16_t *)hmsg->body.kvp_get.data.key,
483 			hmsg->body.kvp_get.data.key_size,
484 			1, &utf_err);
485 		/* utf8 encoding */
486 		umsg->body.kvp_get.data.key_size =
487 		    umsg->body.kvp_get.data.key_size / 2;
488 		break;
489 
490 	case HV_KVP_OP_DELETE:
491 		umsg->body.kvp_delete.key_size =
492 		    utf16_to_utf8(umsg->body.kvp_delete.key,
493 			HV_KVP_EXCHANGE_MAX_KEY_SIZE - 1,
494 			(uint16_t *)hmsg->body.kvp_delete.key,
495 			hmsg->body.kvp_delete.key_size,
496 			1, &utf_err);
497 		/* utf8 encoding */
498 		umsg->body.kvp_delete.key_size =
499 		    umsg->body.kvp_delete.key_size / 2;
500 		break;
501 
502 	case HV_KVP_OP_ENUMERATE:
503 		umsg->body.kvp_enum_data.index =
504 		    hmsg->body.kvp_enum_data.index;
505 		break;
506 
507 	default:
508 		hv_kvp_log_info("%s: daemon_kvp_msg: Invalid operation : %d\n",
509 		    __func__, umsg->kvp_hdr.operation);
510 	}
511 }
512 
513 
514 /*
515  * Prepare a host kvp msg based on user kvp msg (utf8 to utf16)
516  */
517 static int
518 hv_kvp_convert_usermsg_to_hostmsg(struct hv_kvp_msg *umsg, struct hv_kvp_msg *hmsg)
519 {
520 	int hkey_len = 0, hvalue_len = 0, utf_err = 0;
521 	struct hv_kvp_exchg_msg_value *host_exchg_data;
522 	char *key_name, *value;
523 
524 	struct hv_kvp_ip_msg *host_ip_msg = (struct hv_kvp_ip_msg *)hmsg;
525 
526 	switch (hmsg->kvp_hdr.operation) {
527 	case HV_KVP_OP_GET_IP_INFO:
528 		return (hv_kvp_convert_utf8_ipinfo_to_utf16(umsg, host_ip_msg));
529 
530 	case HV_KVP_OP_SET_IP_INFO:
531 	case HV_KVP_OP_SET:
532 	case HV_KVP_OP_DELETE:
533 		return (KVP_SUCCESS);
534 
535 	case HV_KVP_OP_ENUMERATE:
536 		host_exchg_data = &hmsg->body.kvp_enum_data.data;
537 		key_name = umsg->body.kvp_enum_data.data.key;
538 		hkey_len = utf8_to_utf16((uint16_t *)host_exchg_data->key,
539 				((HV_KVP_EXCHANGE_MAX_KEY_SIZE / 2) - 2),
540 				key_name, strlen(key_name),
541 				1, &utf_err);
542 		/* utf16 encoding */
543 		host_exchg_data->key_size = 2 * (hkey_len + 1);
544 		value = umsg->body.kvp_enum_data.data.msg_value.value;
545 		hvalue_len = utf8_to_utf16(
546 				(uint16_t *)host_exchg_data->msg_value.value,
547 				((HV_KVP_EXCHANGE_MAX_VALUE_SIZE / 2) - 2),
548 				value, strlen(value),
549 				1, &utf_err);
550 		host_exchg_data->value_size = 2 * (hvalue_len + 1);
551 		host_exchg_data->value_type = HV_REG_SZ;
552 
553 		if ((hkey_len < 0) || (hvalue_len < 0))
554 			return (HV_KVP_E_FAIL);
555 
556 		return (KVP_SUCCESS);
557 
558 	case HV_KVP_OP_GET:
559 		host_exchg_data = &hmsg->body.kvp_get.data;
560 		value = umsg->body.kvp_get.data.msg_value.value;
561 		hvalue_len = utf8_to_utf16(
562 				(uint16_t *)host_exchg_data->msg_value.value,
563 				((HV_KVP_EXCHANGE_MAX_VALUE_SIZE / 2) - 2),
564 				value, strlen(value),
565 				1, &utf_err);
566 		/* Convert value size to uft16 */
567 		host_exchg_data->value_size = 2 * (hvalue_len + 1);
568 		/* Use values by string */
569 		host_exchg_data->value_type = HV_REG_SZ;
570 
571 		if ((hkey_len < 0) || (hvalue_len < 0))
572 			return (HV_KVP_E_FAIL);
573 
574 		return (KVP_SUCCESS);
575 
576 	default:
577 		return (HV_KVP_E_FAIL);
578 	}
579 }
580 
581 
582 /*
583  * Send the response back to the host.
584  */
585 static void
586 hv_kvp_respond_host(hv_kvp_sc *sc, int error)
587 {
588 	struct hv_vmbus_icmsg_hdr *hv_icmsg_hdrp;
589 
590 	hv_icmsg_hdrp = (struct hv_vmbus_icmsg_hdr *)
591 	    &sc->rcv_buf[sizeof(struct hv_vmbus_pipe_hdr)];
592 
593 	if (error)
594 		error = HV_KVP_E_FAIL;
595 
596 	hv_icmsg_hdrp->status = error;
597 	hv_icmsg_hdrp->icflags = HV_ICMSGHDRFLAG_TRANSACTION | HV_ICMSGHDRFLAG_RESPONSE;
598 
599 	error = hv_vmbus_channel_send_packet(sc->util_sc.hv_dev->channel,
600 			sc->rcv_buf,
601 			sc->host_msg_len, sc->host_msg_id,
602 			HV_VMBUS_PACKET_TYPE_DATA_IN_BAND, 0);
603 
604 	if (error)
605 		hv_kvp_log_info("%s: hv_kvp_respond_host: sendpacket error:%d\n",
606 			__func__, error);
607 }
608 
609 
610 /*
611  * This is the main kvp kernel process that interacts with both user daemon
612  * and the host
613  */
614 static void
615 hv_kvp_send_msg_to_daemon(hv_kvp_sc *sc)
616 {
617 	struct hv_kvp_msg *hmsg = sc->host_kvp_msg;
618 	struct hv_kvp_msg *umsg = &sc->daemon_kvp_msg;
619 
620 	/* Prepare kvp_msg to be sent to user */
621 	hv_kvp_convert_hostmsg_to_usermsg(hmsg, umsg);
622 
623 	/* Send the msg to user via function deamon_read - setting sema */
624 	sema_post(&sc->dev_sema);
625 
626 	/* We should wake up the daemon, in case it's doing poll() */
627 	selwakeup(&sc->hv_kvp_selinfo);
628 }
629 
630 
631 /*
632  * Function to read the kvp request buffer from host
633  * and interact with daemon
634  */
635 static void
636 hv_kvp_process_request(void *context, int pending)
637 {
638 	uint8_t *kvp_buf;
639 	hv_vmbus_channel *channel;
640 	uint32_t recvlen = 0;
641 	uint64_t requestid;
642 	struct hv_vmbus_icmsg_hdr *icmsghdrp;
643 	int ret = 0;
644 	hv_kvp_sc		*sc;
645 
646 	hv_kvp_log_info("%s: entering hv_kvp_process_request\n", __func__);
647 
648 	sc = (hv_kvp_sc*)context;
649 	kvp_buf = sc->util_sc.receive_buffer;;
650 	channel = sc->util_sc.hv_dev->channel;
651 
652 	ret = hv_vmbus_channel_recv_packet(channel, kvp_buf, 2 * PAGE_SIZE,
653 		&recvlen, &requestid);
654 
655 	while ((ret == 0) && (recvlen > 0)) {
656 
657 		icmsghdrp = (struct hv_vmbus_icmsg_hdr *)
658 			&kvp_buf[sizeof(struct hv_vmbus_pipe_hdr)];
659 
660 		hv_kvp_transaction_init(sc, recvlen, requestid, kvp_buf);
661 		if (icmsghdrp->icmsgtype == HV_ICMSGTYPE_NEGOTIATE) {
662 			hv_kvp_negotiate_version(icmsghdrp, NULL, kvp_buf);
663 			hv_kvp_respond_host(sc, ret);
664 
665 			/*
666 			 * It is ok to not acquire the mutex before setting
667 			 * req_in_progress here because negotiation is the
668 			 * first thing that happens and hence there is no
669 			 * chance of a race condition.
670 			 */
671 
672 			sc->req_in_progress = false;
673 			hv_kvp_log_info("%s :version negotiated\n", __func__);
674 
675 		} else {
676 			if (!sc->daemon_busy) {
677 
678 				hv_kvp_log_info("%s: issuing qury to daemon\n", __func__);
679 				mtx_lock(&sc->pending_mutex);
680 				sc->req_timed_out = false;
681 				sc->daemon_busy = true;
682 				mtx_unlock(&sc->pending_mutex);
683 
684 				hv_kvp_send_msg_to_daemon(sc);
685 				hv_kvp_log_info("%s: waiting for daemon\n", __func__);
686 			}
687 
688 			/* Wait 5 seconds for daemon to respond back */
689 			tsleep(sc, 0, "kvpworkitem", 5 * hz);
690 			hv_kvp_log_info("%s: came out of wait\n", __func__);
691 		}
692 
693 		mtx_lock(&sc->pending_mutex);
694 
695 		/* Notice that once req_timed_out is set to true
696 		 * it will remain true until the next request is
697 		 * sent to the daemon. The response from daemon
698 		 * is forwarded to host only when this flag is
699 		 * false.
700 		 */
701 		sc->req_timed_out = true;
702 
703 		/*
704 		 * Cancel request if so need be.
705 		 */
706 		if (hv_kvp_req_in_progress(sc)) {
707 			hv_kvp_log_info("%s: request was still active after wait so failing\n", __func__);
708 			hv_kvp_respond_host(sc, HV_KVP_E_FAIL);
709 			sc->req_in_progress = false;
710 		}
711 
712 		mtx_unlock(&sc->pending_mutex);
713 
714 		/*
715 		 * Try reading next buffer
716 		 */
717 		recvlen = 0;
718 		ret = hv_vmbus_channel_recv_packet(channel, kvp_buf, 2 * PAGE_SIZE,
719 			&recvlen, &requestid);
720 		hv_kvp_log_info("%s: read: context %p, ret =%d, recvlen=%d\n",
721 			__func__, context, ret, recvlen);
722 	}
723 }
724 
725 
726 /*
727  * Callback routine that gets called whenever there is a message from host
728  */
729 static void
730 hv_kvp_callback(void *context)
731 {
732 	hv_kvp_sc *sc = (hv_kvp_sc*)context;
733 	/*
734 	 The first request from host will not be handled until daemon is registered.
735 	 when callback is triggered without a registered daemon, callback just return.
736 	 When a new daemon gets regsitered, this callbcak is trigged from _write op.
737 	*/
738 	if (sc->register_done) {
739 		hv_kvp_log_info("%s: Queuing work item\n", __func__);
740 		taskqueue_enqueue(taskqueue_thread, &sc->task);
741 	}
742 }
743 
744 static int
745 hv_kvp_dev_open(struct cdev *dev, int oflags, int devtype,
746 				struct thread *td)
747 {
748 	hv_kvp_sc *sc = (hv_kvp_sc*)dev->si_drv1;
749 
750 	hv_kvp_log_info("%s: Opened device \"hv_kvp_device\" successfully.\n", __func__);
751 	if (sc->dev_accessed)
752 		return (-EBUSY);
753 
754 	sc->daemon_task = curproc;
755 	sc->dev_accessed = true;
756 	sc->daemon_busy = false;
757 	return (0);
758 }
759 
760 
761 static int
762 hv_kvp_dev_close(struct cdev *dev __unused, int fflag __unused, int devtype __unused,
763 				 struct thread *td __unused)
764 {
765 	hv_kvp_sc *sc = (hv_kvp_sc*)dev->si_drv1;
766 
767 	hv_kvp_log_info("%s: Closing device \"hv_kvp_device\".\n", __func__);
768 	sc->dev_accessed = false;
769 	sc->register_done = false;
770 	return (0);
771 }
772 
773 
774 /*
775  * hv_kvp_daemon read invokes this function
776  * acts as a send to daemon
777  */
778 static int
779 hv_kvp_dev_daemon_read(struct cdev *dev, struct uio *uio, int ioflag __unused)
780 {
781 	size_t amt;
782 	int error = 0;
783 	struct hv_kvp_msg *hv_kvp_dev_buf;
784 	hv_kvp_sc *sc = (hv_kvp_sc*)dev->si_drv1;
785 
786 	/* Check hv_kvp daemon registration status*/
787 	if (!sc->register_done)
788 		return (KVP_ERROR);
789 
790 	sema_wait(&sc->dev_sema);
791 
792 	hv_kvp_dev_buf = malloc(sizeof(*hv_kvp_dev_buf), M_TEMP, M_WAITOK);
793 	memcpy(hv_kvp_dev_buf, &sc->daemon_kvp_msg, sizeof(struct hv_kvp_msg));
794 
795 	amt = MIN(uio->uio_resid, uio->uio_offset >= BUFFERSIZE + 1 ? 0 :
796 		BUFFERSIZE + 1 - uio->uio_offset);
797 
798 	if ((error = uiomove(hv_kvp_dev_buf, amt, uio)) != 0)
799 		hv_kvp_log_info("%s: hv_kvp uiomove read failed!\n", __func__);
800 
801 	free(hv_kvp_dev_buf, M_TEMP);
802 	return (error);
803 }
804 
805 
806 /*
807  * hv_kvp_daemon write invokes this function
808  * acts as a recieve from daemon
809  */
810 static int
811 hv_kvp_dev_daemon_write(struct cdev *dev, struct uio *uio, int ioflag __unused)
812 {
813 	size_t amt;
814 	int error = 0;
815 	struct hv_kvp_msg *hv_kvp_dev_buf;
816 	hv_kvp_sc *sc = (hv_kvp_sc*)dev->si_drv1;
817 
818 	uio->uio_offset = 0;
819 	hv_kvp_dev_buf = malloc(sizeof(*hv_kvp_dev_buf), M_TEMP, M_WAITOK);
820 
821 	amt = MIN(uio->uio_resid, BUFFERSIZE);
822 	error = uiomove(hv_kvp_dev_buf, amt, uio);
823 
824 	if (error != 0) {
825 		free(hv_kvp_dev_buf, M_TEMP);
826 		return (error);
827 	}
828 	memcpy(&sc->daemon_kvp_msg, hv_kvp_dev_buf, sizeof(struct hv_kvp_msg));
829 
830 	free(hv_kvp_dev_buf, M_TEMP);
831 	if (sc->register_done == false) {
832 		if (sc->daemon_kvp_msg.kvp_hdr.operation == HV_KVP_OP_REGISTER) {
833 			sc->register_done = true;
834 			hv_kvp_callback(dev->si_drv1);
835 		}
836 		else {
837 			hv_kvp_log_info("%s, KVP Registration Failed\n", __func__);
838 			return (KVP_ERROR);
839 		}
840 	} else {
841 
842 		mtx_lock(&sc->pending_mutex);
843 
844 		if(!sc->req_timed_out) {
845 			struct hv_kvp_msg *hmsg = sc->host_kvp_msg;
846 			struct hv_kvp_msg *umsg = &sc->daemon_kvp_msg;
847 
848 			hv_kvp_convert_usermsg_to_hostmsg(umsg, hmsg);
849 			hv_kvp_respond_host(sc, KVP_SUCCESS);
850 			wakeup(sc);
851 			sc->req_in_progress = false;
852 		}
853 
854 		sc->daemon_busy = false;
855 		mtx_unlock(&sc->pending_mutex);
856 	}
857 
858 	return (error);
859 }
860 
861 
862 /*
863  * hv_kvp_daemon poll invokes this function to check if data is available
864  * for daemon to read.
865  */
866 static int
867 hv_kvp_dev_daemon_poll(struct cdev *dev, int events, struct thread *td)
868 {
869 	int revents = 0;
870 	hv_kvp_sc *sc = (hv_kvp_sc*)dev->si_drv1;
871 
872 	mtx_lock(&sc->pending_mutex);
873 	/*
874 	 * We check global flag daemon_busy for the data availiability for
875 	 * userland to read. Deamon_busy is set to true before driver has data
876 	 * for daemon to read. It is set to false after daemon sends
877 	 * then response back to driver.
878 	 */
879 	if (sc->daemon_busy == true)
880 		revents = POLLIN;
881 	else
882 		selrecord(td, &sc->hv_kvp_selinfo);
883 
884 	mtx_unlock(&sc->pending_mutex);
885 
886 	return (revents);
887 }
888 
889 static int
890 hv_kvp_probe(device_t dev)
891 {
892 	const char *p = vmbus_get_type(dev);
893 	if (!memcmp(p, &service_guid, sizeof(hv_guid))) {
894 		device_set_desc(dev, "Hyper-V KVP Service");
895 		return BUS_PROBE_DEFAULT;
896 	}
897 
898 	return ENXIO;
899 }
900 
901 static int
902 hv_kvp_attach(device_t dev)
903 {
904 	int error;
905 	struct sysctl_oid_list *child;
906 	struct sysctl_ctx_list *ctx;
907 
908 	hv_kvp_sc *sc = (hv_kvp_sc*)device_get_softc(dev);
909 
910 	sc->util_sc.callback = hv_kvp_callback;
911 	sema_init(&sc->dev_sema, 0, "hv_kvp device semaphore");
912 	mtx_init(&sc->pending_mutex, "hv-kvp pending mutex",
913 		NULL, MTX_DEF);
914 
915 	ctx = device_get_sysctl_ctx(dev);
916 	child = SYSCTL_CHILDREN(device_get_sysctl_tree(dev));
917 
918 	SYSCTL_ADD_INT(ctx, child, OID_AUTO, "hv_kvp_log",
919 	    CTLFLAG_RW, &hv_kvp_log, 0, "Hyperv KVP service log level");
920 
921 	TASK_INIT(&sc->task, 0, hv_kvp_process_request, sc);
922 
923 	/* create character device */
924 	error = make_dev_p(MAKEDEV_CHECKNAME | MAKEDEV_WAITOK,
925 			&sc->hv_kvp_dev,
926 			&hv_kvp_cdevsw,
927 			0,
928 			UID_ROOT,
929 			GID_WHEEL,
930 			0640,
931 			"hv_kvp_dev");
932 
933 	if (error != 0)
934 		return (error);
935 	sc->hv_kvp_dev->si_drv1 = sc;
936 
937 	return hv_util_attach(dev);
938 }
939 
940 static int
941 hv_kvp_detach(device_t dev)
942 {
943 	hv_kvp_sc *sc = (hv_kvp_sc*)device_get_softc(dev);
944 
945 	if (sc->daemon_task != NULL) {
946 		PROC_LOCK(sc->daemon_task);
947 		kern_psignal(sc->daemon_task, SIGKILL);
948 		PROC_UNLOCK(sc->daemon_task);
949 	}
950 
951 	destroy_dev(sc->hv_kvp_dev);
952 	return hv_util_detach(dev);
953 }
954 
955 static device_method_t kvp_methods[] = {
956 	/* Device interface */
957 	DEVMETHOD(device_probe, hv_kvp_probe),
958 	DEVMETHOD(device_attach, hv_kvp_attach),
959 	DEVMETHOD(device_detach, hv_kvp_detach),
960 	{ 0, 0 }
961 };
962 
963 static driver_t kvp_driver = { "hvkvp", kvp_methods, sizeof(hv_kvp_sc)};
964 
965 static devclass_t kvp_devclass;
966 
967 DRIVER_MODULE(hv_kvp, vmbus, kvp_driver, kvp_devclass, NULL, NULL);
968 MODULE_VERSION(hv_kvp, 1);
969 MODULE_DEPEND(hv_kvp, vmbus, 1, 1, 1);
970