xref: /freebsd/sys/dev/hyperv/utilities/hv_kvp.c (revision d96700a6da2afa88607fbd7405ade439424d10d9)
1 /*-
2  * Copyright (c) 2014,2016 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/sema.h>
58 #include <sys/signal.h>
59 #include <sys/syslog.h>
60 #include <sys/systm.h>
61 #include <sys/mutex.h>
62 
63 #include <dev/hyperv/include/hyperv.h>
64 #include <dev/hyperv/utilities/hv_utilreg.h>
65 
66 #include "hv_util.h"
67 #include "unicode.h"
68 #include "hv_kvp.h"
69 #include "vmbus_if.h"
70 
71 /* hv_kvp defines */
72 #define BUFFERSIZE	sizeof(struct hv_kvp_msg)
73 #define KVP_SUCCESS	0
74 #define KVP_ERROR	1
75 #define kvp_hdr		hdr.kvp_hdr
76 
77 /* hv_kvp debug control */
78 static int hv_kvp_log = 0;
79 
80 #define	hv_kvp_log_error(...)	do {				\
81 	if (hv_kvp_log > 0)				\
82 		log(LOG_ERR, "hv_kvp: " __VA_ARGS__);	\
83 } while (0)
84 
85 #define	hv_kvp_log_info(...) do {				\
86 	if (hv_kvp_log > 1)				\
87 		log(LOG_INFO, "hv_kvp: " __VA_ARGS__);		\
88 } while (0)
89 
90 static const struct vmbus_ic_desc vmbus_kvp_descs[] = {
91 	{
92 		.ic_guid = { .hv_guid = {
93 		    0xe7, 0xf4, 0xa0, 0xa9, 0x45, 0x5a, 0x96, 0x4d,
94 		    0xb8, 0x27, 0x8a, 0x84, 0x1e, 0x8c, 0x3,  0xe6 } },
95 		.ic_desc = "Hyper-V KVP"
96 	},
97 	VMBUS_IC_DESC_END
98 };
99 
100 /* character device prototypes */
101 static d_open_t		hv_kvp_dev_open;
102 static d_close_t	hv_kvp_dev_close;
103 static d_read_t		hv_kvp_dev_daemon_read;
104 static d_write_t	hv_kvp_dev_daemon_write;
105 static d_poll_t		hv_kvp_dev_daemon_poll;
106 
107 /* hv_kvp character device structure */
108 static struct cdevsw hv_kvp_cdevsw =
109 {
110 	.d_version	= D_VERSION,
111 	.d_open		= hv_kvp_dev_open,
112 	.d_close	= hv_kvp_dev_close,
113 	.d_read		= hv_kvp_dev_daemon_read,
114 	.d_write	= hv_kvp_dev_daemon_write,
115 	.d_poll		= hv_kvp_dev_daemon_poll,
116 	.d_name		= "hv_kvp_dev",
117 };
118 
119 
120 /*
121  * Global state to track and synchronize multiple
122  * KVP transaction requests from the host.
123  */
124 typedef struct hv_kvp_sc {
125 	struct hv_util_sc	util_sc;
126 	device_t		dev;
127 
128 	/* Unless specified the pending mutex should be
129 	 * used to alter the values of the following parameters:
130 	 * 1. req_in_progress
131 	 * 2. req_timed_out
132 	 */
133 	struct mtx		pending_mutex;
134 
135 	struct task		task;
136 
137 	/* To track if transaction is active or not */
138 	boolean_t		req_in_progress;
139 	/* Tracks if daemon did not reply back in time */
140 	boolean_t		req_timed_out;
141 	/* Tracks if daemon is serving a request currently */
142 	boolean_t		daemon_busy;
143 
144 	/* Length of host message */
145 	uint32_t		host_msg_len;
146 
147 	/* Host message id */
148 	uint64_t		host_msg_id;
149 
150 	/* Current kvp message from the host */
151 	struct hv_kvp_msg	*host_kvp_msg;
152 
153 	 /* Current kvp message for daemon */
154 	struct hv_kvp_msg	daemon_kvp_msg;
155 
156 	/* Rcv buffer for communicating with the host*/
157 	uint8_t			*rcv_buf;
158 
159 	/* Device semaphore to control communication */
160 	struct sema		dev_sema;
161 
162 	/* Indicates if daemon registered with driver */
163 	boolean_t		register_done;
164 
165 	/* Character device status */
166 	boolean_t		dev_accessed;
167 
168 	struct cdev *hv_kvp_dev;
169 
170 	struct proc *daemon_task;
171 
172 	struct selinfo hv_kvp_selinfo;
173 } hv_kvp_sc;
174 
175 /* hv_kvp prototypes */
176 static int	hv_kvp_req_in_progress(hv_kvp_sc *sc);
177 static void	hv_kvp_transaction_init(hv_kvp_sc *sc, uint32_t, uint64_t, uint8_t *);
178 static void	hv_kvp_send_msg_to_daemon(hv_kvp_sc *sc);
179 static void	hv_kvp_process_request(void *context, int pending);
180 
181 /*
182  * hv_kvp low level functions
183  */
184 
185 /*
186  * Check if kvp transaction is in progres
187  */
188 static int
189 hv_kvp_req_in_progress(hv_kvp_sc *sc)
190 {
191 
192 	return (sc->req_in_progress);
193 }
194 
195 
196 /*
197  * This routine is called whenever a message is received from the host
198  */
199 static void
200 hv_kvp_transaction_init(hv_kvp_sc *sc, uint32_t rcv_len,
201 			uint64_t request_id, uint8_t *rcv_buf)
202 {
203 
204 	/* Store all the relevant message details in the global structure */
205 	/* Do not need to use mutex for req_in_progress here */
206 	sc->req_in_progress = true;
207 	sc->host_msg_len = rcv_len;
208 	sc->host_msg_id = request_id;
209 	sc->rcv_buf = rcv_buf;
210 	sc->host_kvp_msg = (struct hv_kvp_msg *)&rcv_buf[
211 		sizeof(struct hv_vmbus_pipe_hdr) +
212 		sizeof(struct hv_vmbus_icmsg_hdr)];
213 }
214 
215 
216 /*
217  * hv_kvp - version neogtiation function
218  */
219 static void
220 hv_kvp_negotiate_version(struct hv_vmbus_icmsg_hdr *icmsghdrp, uint8_t *buf)
221 {
222 	struct hv_vmbus_icmsg_negotiate *negop;
223 	int icframe_vercnt;
224 	int icmsg_vercnt;
225 
226 	icmsghdrp->icmsgsize = 0x10;
227 
228 	negop = (struct hv_vmbus_icmsg_negotiate *)&buf[
229 		sizeof(struct hv_vmbus_pipe_hdr) +
230 		sizeof(struct hv_vmbus_icmsg_hdr)];
231 	icframe_vercnt = negop->icframe_vercnt;
232 	icmsg_vercnt = negop->icmsg_vercnt;
233 
234 	/*
235 	 * Select the framework version number we will support
236 	 */
237 	if ((icframe_vercnt >= 2) && (negop->icversion_data[1].major == 3)) {
238 		icframe_vercnt = 3;
239 		if (icmsg_vercnt > 2)
240 			icmsg_vercnt = 4;
241 		else
242 			icmsg_vercnt = 3;
243 	} else {
244 		icframe_vercnt = 1;
245 		icmsg_vercnt = 1;
246 	}
247 
248 	negop->icframe_vercnt = 1;
249 	negop->icmsg_vercnt = 1;
250 	negop->icversion_data[0].major = icframe_vercnt;
251 	negop->icversion_data[0].minor = 0;
252 	negop->icversion_data[1].major = icmsg_vercnt;
253 	negop->icversion_data[1].minor = 0;
254 }
255 
256 
257 /*
258  * Convert ip related info in umsg from utf8 to utf16 and store in hmsg
259  */
260 static int
261 hv_kvp_convert_utf8_ipinfo_to_utf16(struct hv_kvp_msg *umsg,
262 				    struct hv_kvp_ip_msg *host_ip_msg)
263 {
264 	int err_ip, err_subnet, err_gway, err_dns, err_adap;
265 	int UNUSED_FLAG = 1;
266 
267 	utf8_to_utf16((uint16_t *)host_ip_msg->kvp_ip_val.ip_addr,
268 	    MAX_IP_ADDR_SIZE,
269 	    (char *)umsg->body.kvp_ip_val.ip_addr,
270 	    strlen((char *)umsg->body.kvp_ip_val.ip_addr),
271 	    UNUSED_FLAG,
272 	    &err_ip);
273 	utf8_to_utf16((uint16_t *)host_ip_msg->kvp_ip_val.sub_net,
274 	    MAX_IP_ADDR_SIZE,
275 	    (char *)umsg->body.kvp_ip_val.sub_net,
276 	    strlen((char *)umsg->body.kvp_ip_val.sub_net),
277 	    UNUSED_FLAG,
278 	    &err_subnet);
279 	utf8_to_utf16((uint16_t *)host_ip_msg->kvp_ip_val.gate_way,
280 	    MAX_GATEWAY_SIZE,
281 	    (char *)umsg->body.kvp_ip_val.gate_way,
282 	    strlen((char *)umsg->body.kvp_ip_val.gate_way),
283 	    UNUSED_FLAG,
284 	    &err_gway);
285 	utf8_to_utf16((uint16_t *)host_ip_msg->kvp_ip_val.dns_addr,
286 	    MAX_IP_ADDR_SIZE,
287 	    (char *)umsg->body.kvp_ip_val.dns_addr,
288 	    strlen((char *)umsg->body.kvp_ip_val.dns_addr),
289 	    UNUSED_FLAG,
290 	    &err_dns);
291 	utf8_to_utf16((uint16_t *)host_ip_msg->kvp_ip_val.adapter_id,
292 	    MAX_IP_ADDR_SIZE,
293 	    (char *)umsg->body.kvp_ip_val.adapter_id,
294 	    strlen((char *)umsg->body.kvp_ip_val.adapter_id),
295 	    UNUSED_FLAG,
296 	    &err_adap);
297 
298 	host_ip_msg->kvp_ip_val.dhcp_enabled = umsg->body.kvp_ip_val.dhcp_enabled;
299 	host_ip_msg->kvp_ip_val.addr_family = umsg->body.kvp_ip_val.addr_family;
300 
301 	return (err_ip | err_subnet | err_gway | err_dns | err_adap);
302 }
303 
304 
305 /*
306  * Convert ip related info in hmsg from utf16 to utf8 and store in umsg
307  */
308 static int
309 hv_kvp_convert_utf16_ipinfo_to_utf8(struct hv_kvp_ip_msg *host_ip_msg,
310 				    struct hv_kvp_msg *umsg)
311 {
312 	int err_ip, err_subnet, err_gway, err_dns, err_adap;
313 	int UNUSED_FLAG = 1;
314 	device_t *devs;
315 	int devcnt;
316 
317 	/* IP Address */
318 	utf16_to_utf8((char *)umsg->body.kvp_ip_val.ip_addr,
319 	    MAX_IP_ADDR_SIZE,
320 	    (uint16_t *)host_ip_msg->kvp_ip_val.ip_addr,
321 	    MAX_IP_ADDR_SIZE,
322 	    UNUSED_FLAG,
323 	    &err_ip);
324 
325 	/* Adapter ID : GUID */
326 	utf16_to_utf8((char *)umsg->body.kvp_ip_val.adapter_id,
327 	    MAX_ADAPTER_ID_SIZE,
328 	    (uint16_t *)host_ip_msg->kvp_ip_val.adapter_id,
329 	    MAX_ADAPTER_ID_SIZE,
330 	    UNUSED_FLAG,
331 	    &err_adap);
332 
333 	if (devclass_get_devices(devclass_find("hn"), &devs, &devcnt) == 0) {
334 		for (devcnt = devcnt - 1; devcnt >= 0; devcnt--) {
335 			/* XXX access other driver's softc?  are you kidding? */
336 			device_t dev = devs[devcnt];
337 			struct vmbus_channel *chan;
338 			char buf[HYPERV_GUID_STRLEN];
339 
340 			/*
341 			 * Trying to find GUID of Network Device
342 			 */
343 			chan = vmbus_get_channel(dev);
344 			hyperv_guid2str(vmbus_chan_guid_inst(chan),
345 			    buf, sizeof(buf));
346 
347 			if (strncmp(buf, (char *)umsg->body.kvp_ip_val.adapter_id,
348 			    HYPERV_GUID_STRLEN - 1) == 0) {
349 				strlcpy((char *)umsg->body.kvp_ip_val.adapter_id,
350 				    device_get_nameunit(dev), MAX_ADAPTER_ID_SIZE);
351 				break;
352 			}
353 		}
354 		free(devs, M_TEMP);
355 	}
356 
357 	/* Address Family , DHCP , SUBNET, Gateway, DNS */
358 	umsg->kvp_hdr.operation = host_ip_msg->operation;
359 	umsg->body.kvp_ip_val.addr_family = host_ip_msg->kvp_ip_val.addr_family;
360 	umsg->body.kvp_ip_val.dhcp_enabled = host_ip_msg->kvp_ip_val.dhcp_enabled;
361 	utf16_to_utf8((char *)umsg->body.kvp_ip_val.sub_net, MAX_IP_ADDR_SIZE,
362 	    (uint16_t *)host_ip_msg->kvp_ip_val.sub_net,
363 	    MAX_IP_ADDR_SIZE,
364 	    UNUSED_FLAG,
365 	    &err_subnet);
366 
367 	utf16_to_utf8((char *)umsg->body.kvp_ip_val.gate_way, MAX_GATEWAY_SIZE,
368 	    (uint16_t *)host_ip_msg->kvp_ip_val.gate_way,
369 	    MAX_GATEWAY_SIZE,
370 	    UNUSED_FLAG,
371 	    &err_gway);
372 
373 	utf16_to_utf8((char *)umsg->body.kvp_ip_val.dns_addr, MAX_IP_ADDR_SIZE,
374 	    (uint16_t *)host_ip_msg->kvp_ip_val.dns_addr,
375 	    MAX_IP_ADDR_SIZE,
376 	    UNUSED_FLAG,
377 	    &err_dns);
378 
379 	return (err_ip | err_subnet | err_gway | err_dns | err_adap);
380 }
381 
382 
383 /*
384  * Prepare a user kvp msg based on host kvp msg (utf16 to utf8)
385  * Ensure utf16_utf8 takes care of the additional string terminating char!!
386  */
387 static void
388 hv_kvp_convert_hostmsg_to_usermsg(struct hv_kvp_msg *hmsg, struct hv_kvp_msg *umsg)
389 {
390 	int utf_err = 0;
391 	uint32_t value_type;
392 	struct hv_kvp_ip_msg *host_ip_msg;
393 
394 	host_ip_msg = (struct hv_kvp_ip_msg*)hmsg;
395 	memset(umsg, 0, sizeof(struct hv_kvp_msg));
396 
397 	umsg->kvp_hdr.operation = hmsg->kvp_hdr.operation;
398 	umsg->kvp_hdr.pool = hmsg->kvp_hdr.pool;
399 
400 	switch (umsg->kvp_hdr.operation) {
401 	case HV_KVP_OP_SET_IP_INFO:
402 		hv_kvp_convert_utf16_ipinfo_to_utf8(host_ip_msg, umsg);
403 		break;
404 
405 	case HV_KVP_OP_GET_IP_INFO:
406 		utf16_to_utf8((char *)umsg->body.kvp_ip_val.adapter_id,
407 		    MAX_ADAPTER_ID_SIZE,
408 		    (uint16_t *)host_ip_msg->kvp_ip_val.adapter_id,
409 		    MAX_ADAPTER_ID_SIZE, 1, &utf_err);
410 
411 		umsg->body.kvp_ip_val.addr_family =
412 		    host_ip_msg->kvp_ip_val.addr_family;
413 		break;
414 
415 	case HV_KVP_OP_SET:
416 		value_type = hmsg->body.kvp_set.data.value_type;
417 
418 		switch (value_type) {
419 		case HV_REG_SZ:
420 			umsg->body.kvp_set.data.value_size =
421 			    utf16_to_utf8(
422 				(char *)umsg->body.kvp_set.data.msg_value.value,
423 				HV_KVP_EXCHANGE_MAX_VALUE_SIZE - 1,
424 				(uint16_t *)hmsg->body.kvp_set.data.msg_value.value,
425 				hmsg->body.kvp_set.data.value_size,
426 				1, &utf_err);
427 			/* utf8 encoding */
428 			umsg->body.kvp_set.data.value_size =
429 			    umsg->body.kvp_set.data.value_size / 2;
430 			break;
431 
432 		case HV_REG_U32:
433 			umsg->body.kvp_set.data.value_size =
434 			    sprintf(umsg->body.kvp_set.data.msg_value.value, "%d",
435 				hmsg->body.kvp_set.data.msg_value.value_u32) + 1;
436 			break;
437 
438 		case HV_REG_U64:
439 			umsg->body.kvp_set.data.value_size =
440 			    sprintf(umsg->body.kvp_set.data.msg_value.value, "%llu",
441 				(unsigned long long)
442 				hmsg->body.kvp_set.data.msg_value.value_u64) + 1;
443 			break;
444 		}
445 
446 		umsg->body.kvp_set.data.key_size =
447 		    utf16_to_utf8(
448 			umsg->body.kvp_set.data.key,
449 			HV_KVP_EXCHANGE_MAX_KEY_SIZE - 1,
450 			(uint16_t *)hmsg->body.kvp_set.data.key,
451 			hmsg->body.kvp_set.data.key_size,
452 			1, &utf_err);
453 
454 		/* utf8 encoding */
455 		umsg->body.kvp_set.data.key_size =
456 		    umsg->body.kvp_set.data.key_size / 2;
457 		break;
458 
459 	case HV_KVP_OP_GET:
460 		umsg->body.kvp_get.data.key_size =
461 		    utf16_to_utf8(umsg->body.kvp_get.data.key,
462 			HV_KVP_EXCHANGE_MAX_KEY_SIZE - 1,
463 			(uint16_t *)hmsg->body.kvp_get.data.key,
464 			hmsg->body.kvp_get.data.key_size,
465 			1, &utf_err);
466 		/* utf8 encoding */
467 		umsg->body.kvp_get.data.key_size =
468 		    umsg->body.kvp_get.data.key_size / 2;
469 		break;
470 
471 	case HV_KVP_OP_DELETE:
472 		umsg->body.kvp_delete.key_size =
473 		    utf16_to_utf8(umsg->body.kvp_delete.key,
474 			HV_KVP_EXCHANGE_MAX_KEY_SIZE - 1,
475 			(uint16_t *)hmsg->body.kvp_delete.key,
476 			hmsg->body.kvp_delete.key_size,
477 			1, &utf_err);
478 		/* utf8 encoding */
479 		umsg->body.kvp_delete.key_size =
480 		    umsg->body.kvp_delete.key_size / 2;
481 		break;
482 
483 	case HV_KVP_OP_ENUMERATE:
484 		umsg->body.kvp_enum_data.index =
485 		    hmsg->body.kvp_enum_data.index;
486 		break;
487 
488 	default:
489 		hv_kvp_log_info("%s: daemon_kvp_msg: Invalid operation : %d\n",
490 		    __func__, umsg->kvp_hdr.operation);
491 	}
492 }
493 
494 
495 /*
496  * Prepare a host kvp msg based on user kvp msg (utf8 to utf16)
497  */
498 static int
499 hv_kvp_convert_usermsg_to_hostmsg(struct hv_kvp_msg *umsg, struct hv_kvp_msg *hmsg)
500 {
501 	int hkey_len = 0, hvalue_len = 0, utf_err = 0;
502 	struct hv_kvp_exchg_msg_value *host_exchg_data;
503 	char *key_name, *value;
504 
505 	struct hv_kvp_ip_msg *host_ip_msg = (struct hv_kvp_ip_msg *)hmsg;
506 
507 	switch (hmsg->kvp_hdr.operation) {
508 	case HV_KVP_OP_GET_IP_INFO:
509 		return (hv_kvp_convert_utf8_ipinfo_to_utf16(umsg, host_ip_msg));
510 
511 	case HV_KVP_OP_SET_IP_INFO:
512 	case HV_KVP_OP_SET:
513 	case HV_KVP_OP_DELETE:
514 		return (KVP_SUCCESS);
515 
516 	case HV_KVP_OP_ENUMERATE:
517 		host_exchg_data = &hmsg->body.kvp_enum_data.data;
518 		key_name = umsg->body.kvp_enum_data.data.key;
519 		hkey_len = utf8_to_utf16((uint16_t *)host_exchg_data->key,
520 				((HV_KVP_EXCHANGE_MAX_KEY_SIZE / 2) - 2),
521 				key_name, strlen(key_name),
522 				1, &utf_err);
523 		/* utf16 encoding */
524 		host_exchg_data->key_size = 2 * (hkey_len + 1);
525 		value = umsg->body.kvp_enum_data.data.msg_value.value;
526 		hvalue_len = utf8_to_utf16(
527 				(uint16_t *)host_exchg_data->msg_value.value,
528 				((HV_KVP_EXCHANGE_MAX_VALUE_SIZE / 2) - 2),
529 				value, strlen(value),
530 				1, &utf_err);
531 		host_exchg_data->value_size = 2 * (hvalue_len + 1);
532 		host_exchg_data->value_type = HV_REG_SZ;
533 
534 		if ((hkey_len < 0) || (hvalue_len < 0))
535 			return (HV_KVP_E_FAIL);
536 
537 		return (KVP_SUCCESS);
538 
539 	case HV_KVP_OP_GET:
540 		host_exchg_data = &hmsg->body.kvp_get.data;
541 		value = umsg->body.kvp_get.data.msg_value.value;
542 		hvalue_len = utf8_to_utf16(
543 				(uint16_t *)host_exchg_data->msg_value.value,
544 				((HV_KVP_EXCHANGE_MAX_VALUE_SIZE / 2) - 2),
545 				value, strlen(value),
546 				1, &utf_err);
547 		/* Convert value size to uft16 */
548 		host_exchg_data->value_size = 2 * (hvalue_len + 1);
549 		/* Use values by string */
550 		host_exchg_data->value_type = HV_REG_SZ;
551 
552 		if ((hkey_len < 0) || (hvalue_len < 0))
553 			return (HV_KVP_E_FAIL);
554 
555 		return (KVP_SUCCESS);
556 
557 	default:
558 		return (HV_KVP_E_FAIL);
559 	}
560 }
561 
562 
563 /*
564  * Send the response back to the host.
565  */
566 static void
567 hv_kvp_respond_host(hv_kvp_sc *sc, int error)
568 {
569 	struct hv_vmbus_icmsg_hdr *hv_icmsg_hdrp;
570 
571 	hv_icmsg_hdrp = (struct hv_vmbus_icmsg_hdr *)
572 	    &sc->rcv_buf[sizeof(struct hv_vmbus_pipe_hdr)];
573 
574 	if (error)
575 		error = HV_KVP_E_FAIL;
576 
577 	hv_icmsg_hdrp->status = error;
578 	hv_icmsg_hdrp->icflags = HV_ICMSGHDRFLAG_TRANSACTION | HV_ICMSGHDRFLAG_RESPONSE;
579 
580 	error = vmbus_chan_send(vmbus_get_channel(sc->dev),
581 	    VMBUS_CHANPKT_TYPE_INBAND, 0, sc->rcv_buf, sc->host_msg_len,
582 	    sc->host_msg_id);
583 	if (error)
584 		hv_kvp_log_info("%s: hv_kvp_respond_host: sendpacket error:%d\n",
585 			__func__, error);
586 }
587 
588 
589 /*
590  * This is the main kvp kernel process that interacts with both user daemon
591  * and the host
592  */
593 static void
594 hv_kvp_send_msg_to_daemon(hv_kvp_sc *sc)
595 {
596 	struct hv_kvp_msg *hmsg = sc->host_kvp_msg;
597 	struct hv_kvp_msg *umsg = &sc->daemon_kvp_msg;
598 
599 	/* Prepare kvp_msg to be sent to user */
600 	hv_kvp_convert_hostmsg_to_usermsg(hmsg, umsg);
601 
602 	/* Send the msg to user via function deamon_read - setting sema */
603 	sema_post(&sc->dev_sema);
604 
605 	/* We should wake up the daemon, in case it's doing poll() */
606 	selwakeup(&sc->hv_kvp_selinfo);
607 }
608 
609 
610 /*
611  * Function to read the kvp request buffer from host
612  * and interact with daemon
613  */
614 static void
615 hv_kvp_process_request(void *context, int pending)
616 {
617 	uint8_t *kvp_buf;
618 	struct vmbus_channel *channel;
619 	uint32_t recvlen = 0;
620 	uint64_t requestid;
621 	struct hv_vmbus_icmsg_hdr *icmsghdrp;
622 	int ret = 0;
623 	hv_kvp_sc		*sc;
624 
625 	hv_kvp_log_info("%s: entering hv_kvp_process_request\n", __func__);
626 
627 	sc = (hv_kvp_sc*)context;
628 	kvp_buf = sc->util_sc.receive_buffer;
629 	channel = vmbus_get_channel(sc->dev);
630 
631 	recvlen = sc->util_sc.ic_buflen;
632 	ret = vmbus_chan_recv(channel, kvp_buf, &recvlen, &requestid);
633 	KASSERT(ret != ENOBUFS, ("hvkvp recvbuf is not large enough"));
634 	/* XXX check recvlen to make sure that it contains enough data */
635 
636 	while ((ret == 0) && (recvlen > 0)) {
637 
638 		icmsghdrp = (struct hv_vmbus_icmsg_hdr *)
639 			&kvp_buf[sizeof(struct hv_vmbus_pipe_hdr)];
640 
641 		hv_kvp_transaction_init(sc, recvlen, requestid, kvp_buf);
642 		if (icmsghdrp->icmsgtype == HV_ICMSGTYPE_NEGOTIATE) {
643 			hv_kvp_negotiate_version(icmsghdrp, kvp_buf);
644 			hv_kvp_respond_host(sc, ret);
645 
646 			/*
647 			 * It is ok to not acquire the mutex before setting
648 			 * req_in_progress here because negotiation is the
649 			 * first thing that happens and hence there is no
650 			 * chance of a race condition.
651 			 */
652 
653 			sc->req_in_progress = false;
654 			hv_kvp_log_info("%s :version negotiated\n", __func__);
655 
656 		} else {
657 			if (!sc->daemon_busy) {
658 
659 				hv_kvp_log_info("%s: issuing qury to daemon\n", __func__);
660 				mtx_lock(&sc->pending_mutex);
661 				sc->req_timed_out = false;
662 				sc->daemon_busy = true;
663 				mtx_unlock(&sc->pending_mutex);
664 
665 				hv_kvp_send_msg_to_daemon(sc);
666 				hv_kvp_log_info("%s: waiting for daemon\n", __func__);
667 			}
668 
669 			/* Wait 5 seconds for daemon to respond back */
670 			tsleep(sc, 0, "kvpworkitem", 5 * hz);
671 			hv_kvp_log_info("%s: came out of wait\n", __func__);
672 		}
673 
674 		mtx_lock(&sc->pending_mutex);
675 
676 		/* Notice that once req_timed_out is set to true
677 		 * it will remain true until the next request is
678 		 * sent to the daemon. The response from daemon
679 		 * is forwarded to host only when this flag is
680 		 * false.
681 		 */
682 		sc->req_timed_out = true;
683 
684 		/*
685 		 * Cancel request if so need be.
686 		 */
687 		if (hv_kvp_req_in_progress(sc)) {
688 			hv_kvp_log_info("%s: request was still active after wait so failing\n", __func__);
689 			hv_kvp_respond_host(sc, HV_KVP_E_FAIL);
690 			sc->req_in_progress = false;
691 		}
692 
693 		mtx_unlock(&sc->pending_mutex);
694 
695 		/*
696 		 * Try reading next buffer
697 		 */
698 		recvlen = sc->util_sc.ic_buflen;
699 		ret = vmbus_chan_recv(channel, kvp_buf, &recvlen, &requestid);
700 		KASSERT(ret != ENOBUFS, ("hvkvp recvbuf is not large enough"));
701 		/* XXX check recvlen to make sure that it contains enough data */
702 
703 		hv_kvp_log_info("%s: read: context %p, ret =%d, recvlen=%d\n",
704 			__func__, context, ret, recvlen);
705 	}
706 }
707 
708 
709 /*
710  * Callback routine that gets called whenever there is a message from host
711  */
712 static void
713 hv_kvp_callback(struct vmbus_channel *chan __unused, void *context)
714 {
715 	hv_kvp_sc *sc = (hv_kvp_sc*)context;
716 	/*
717 	 The first request from host will not be handled until daemon is registered.
718 	 when callback is triggered without a registered daemon, callback just return.
719 	 When a new daemon gets regsitered, this callbcak is trigged from _write op.
720 	*/
721 	if (sc->register_done) {
722 		hv_kvp_log_info("%s: Queuing work item\n", __func__);
723 		taskqueue_enqueue(taskqueue_thread, &sc->task);
724 	}
725 }
726 
727 static int
728 hv_kvp_dev_open(struct cdev *dev, int oflags, int devtype,
729 				struct thread *td)
730 {
731 	hv_kvp_sc *sc = (hv_kvp_sc*)dev->si_drv1;
732 
733 	hv_kvp_log_info("%s: Opened device \"hv_kvp_device\" successfully.\n", __func__);
734 	if (sc->dev_accessed)
735 		return (-EBUSY);
736 
737 	sc->daemon_task = curproc;
738 	sc->dev_accessed = true;
739 	sc->daemon_busy = false;
740 	return (0);
741 }
742 
743 
744 static int
745 hv_kvp_dev_close(struct cdev *dev __unused, int fflag __unused, int devtype __unused,
746 				 struct thread *td __unused)
747 {
748 	hv_kvp_sc *sc = (hv_kvp_sc*)dev->si_drv1;
749 
750 	hv_kvp_log_info("%s: Closing device \"hv_kvp_device\".\n", __func__);
751 	sc->dev_accessed = false;
752 	sc->register_done = false;
753 	return (0);
754 }
755 
756 
757 /*
758  * hv_kvp_daemon read invokes this function
759  * acts as a send to daemon
760  */
761 static int
762 hv_kvp_dev_daemon_read(struct cdev *dev, struct uio *uio, int ioflag __unused)
763 {
764 	size_t amt;
765 	int error = 0;
766 	struct hv_kvp_msg *hv_kvp_dev_buf;
767 	hv_kvp_sc *sc = (hv_kvp_sc*)dev->si_drv1;
768 
769 	/* Check hv_kvp daemon registration status*/
770 	if (!sc->register_done)
771 		return (KVP_ERROR);
772 
773 	sema_wait(&sc->dev_sema);
774 
775 	hv_kvp_dev_buf = malloc(sizeof(*hv_kvp_dev_buf), M_TEMP, M_WAITOK);
776 	memcpy(hv_kvp_dev_buf, &sc->daemon_kvp_msg, sizeof(struct hv_kvp_msg));
777 
778 	amt = MIN(uio->uio_resid, uio->uio_offset >= BUFFERSIZE + 1 ? 0 :
779 		BUFFERSIZE + 1 - uio->uio_offset);
780 
781 	if ((error = uiomove(hv_kvp_dev_buf, amt, uio)) != 0)
782 		hv_kvp_log_info("%s: hv_kvp uiomove read failed!\n", __func__);
783 
784 	free(hv_kvp_dev_buf, M_TEMP);
785 	return (error);
786 }
787 
788 
789 /*
790  * hv_kvp_daemon write invokes this function
791  * acts as a receive from daemon
792  */
793 static int
794 hv_kvp_dev_daemon_write(struct cdev *dev, struct uio *uio, int ioflag __unused)
795 {
796 	size_t amt;
797 	int error = 0;
798 	struct hv_kvp_msg *hv_kvp_dev_buf;
799 	hv_kvp_sc *sc = (hv_kvp_sc*)dev->si_drv1;
800 
801 	uio->uio_offset = 0;
802 	hv_kvp_dev_buf = malloc(sizeof(*hv_kvp_dev_buf), M_TEMP, M_WAITOK);
803 
804 	amt = MIN(uio->uio_resid, BUFFERSIZE);
805 	error = uiomove(hv_kvp_dev_buf, amt, uio);
806 
807 	if (error != 0) {
808 		free(hv_kvp_dev_buf, M_TEMP);
809 		return (error);
810 	}
811 	memcpy(&sc->daemon_kvp_msg, hv_kvp_dev_buf, sizeof(struct hv_kvp_msg));
812 
813 	free(hv_kvp_dev_buf, M_TEMP);
814 	if (sc->register_done == false) {
815 		if (sc->daemon_kvp_msg.kvp_hdr.operation == HV_KVP_OP_REGISTER) {
816 			sc->register_done = true;
817 			hv_kvp_callback(vmbus_get_channel(sc->dev), dev->si_drv1);
818 		}
819 		else {
820 			hv_kvp_log_info("%s, KVP Registration Failed\n", __func__);
821 			return (KVP_ERROR);
822 		}
823 	} else {
824 
825 		mtx_lock(&sc->pending_mutex);
826 
827 		if(!sc->req_timed_out) {
828 			struct hv_kvp_msg *hmsg = sc->host_kvp_msg;
829 			struct hv_kvp_msg *umsg = &sc->daemon_kvp_msg;
830 
831 			hv_kvp_convert_usermsg_to_hostmsg(umsg, hmsg);
832 			hv_kvp_respond_host(sc, KVP_SUCCESS);
833 			wakeup(sc);
834 			sc->req_in_progress = false;
835 		}
836 
837 		sc->daemon_busy = false;
838 		mtx_unlock(&sc->pending_mutex);
839 	}
840 
841 	return (error);
842 }
843 
844 
845 /*
846  * hv_kvp_daemon poll invokes this function to check if data is available
847  * for daemon to read.
848  */
849 static int
850 hv_kvp_dev_daemon_poll(struct cdev *dev, int events, struct thread *td)
851 {
852 	int revents = 0;
853 	hv_kvp_sc *sc = (hv_kvp_sc*)dev->si_drv1;
854 
855 	mtx_lock(&sc->pending_mutex);
856 	/*
857 	 * We check global flag daemon_busy for the data availiability for
858 	 * userland to read. Deamon_busy is set to true before driver has data
859 	 * for daemon to read. It is set to false after daemon sends
860 	 * then response back to driver.
861 	 */
862 	if (sc->daemon_busy == true)
863 		revents = POLLIN;
864 	else
865 		selrecord(td, &sc->hv_kvp_selinfo);
866 
867 	mtx_unlock(&sc->pending_mutex);
868 
869 	return (revents);
870 }
871 
872 static int
873 hv_kvp_probe(device_t dev)
874 {
875 
876 	return (vmbus_ic_probe(dev, vmbus_kvp_descs));
877 }
878 
879 static int
880 hv_kvp_attach(device_t dev)
881 {
882 	int error;
883 	struct sysctl_oid_list *child;
884 	struct sysctl_ctx_list *ctx;
885 
886 	hv_kvp_sc *sc = (hv_kvp_sc*)device_get_softc(dev);
887 
888 	sc->dev = dev;
889 	sema_init(&sc->dev_sema, 0, "hv_kvp device semaphore");
890 	mtx_init(&sc->pending_mutex, "hv-kvp pending mutex",
891 		NULL, MTX_DEF);
892 
893 	ctx = device_get_sysctl_ctx(dev);
894 	child = SYSCTL_CHILDREN(device_get_sysctl_tree(dev));
895 
896 	SYSCTL_ADD_INT(ctx, child, OID_AUTO, "hv_kvp_log",
897 	    CTLFLAG_RW, &hv_kvp_log, 0, "Hyperv KVP service log level");
898 
899 	TASK_INIT(&sc->task, 0, hv_kvp_process_request, sc);
900 
901 	/* create character device */
902 	error = make_dev_p(MAKEDEV_CHECKNAME | MAKEDEV_WAITOK,
903 			&sc->hv_kvp_dev,
904 			&hv_kvp_cdevsw,
905 			0,
906 			UID_ROOT,
907 			GID_WHEEL,
908 			0640,
909 			"hv_kvp_dev");
910 
911 	if (error != 0)
912 		return (error);
913 	sc->hv_kvp_dev->si_drv1 = sc;
914 
915 	return hv_util_attach(dev, hv_kvp_callback);
916 }
917 
918 static int
919 hv_kvp_detach(device_t dev)
920 {
921 	hv_kvp_sc *sc = (hv_kvp_sc*)device_get_softc(dev);
922 
923 	if (sc->daemon_task != NULL) {
924 		PROC_LOCK(sc->daemon_task);
925 		kern_psignal(sc->daemon_task, SIGKILL);
926 		PROC_UNLOCK(sc->daemon_task);
927 	}
928 
929 	destroy_dev(sc->hv_kvp_dev);
930 	return hv_util_detach(dev);
931 }
932 
933 static device_method_t kvp_methods[] = {
934 	/* Device interface */
935 	DEVMETHOD(device_probe, hv_kvp_probe),
936 	DEVMETHOD(device_attach, hv_kvp_attach),
937 	DEVMETHOD(device_detach, hv_kvp_detach),
938 	{ 0, 0 }
939 };
940 
941 static driver_t kvp_driver = { "hvkvp", kvp_methods, sizeof(hv_kvp_sc)};
942 
943 static devclass_t kvp_devclass;
944 
945 DRIVER_MODULE(hv_kvp, vmbus, kvp_driver, kvp_devclass, NULL, NULL);
946 MODULE_VERSION(hv_kvp, 1);
947 MODULE_DEPEND(hv_kvp, vmbus, 1, 1, 1);
948