xref: /freebsd/sys/dev/hyperv/utilities/hv_kvp.c (revision 430f7286a566b1407c7b32ce13585caf5aa59b92)
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/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 parameters:
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 	struct hv_device *hv_dev;       /* GUID Data Structure */
308 	hn_softc_t *sc;                 /* hn softc structure  */
309 	char if_name[4];
310 	char buf[39];
311 
312 	device_t *devs;
313 	int devcnt;
314 
315 	/* IP Address */
316 	utf16_to_utf8((char *)umsg->body.kvp_ip_val.ip_addr,
317 	    MAX_IP_ADDR_SIZE,
318 	    (uint16_t *)host_ip_msg->kvp_ip_val.ip_addr,
319 	    MAX_IP_ADDR_SIZE,
320 	    UNUSED_FLAG,
321 	    &err_ip);
322 
323 	/* Adapter ID : GUID */
324 	utf16_to_utf8((char *)umsg->body.kvp_ip_val.adapter_id,
325 	    MAX_ADAPTER_ID_SIZE,
326 	    (uint16_t *)host_ip_msg->kvp_ip_val.adapter_id,
327 	    MAX_ADAPTER_ID_SIZE,
328 	    UNUSED_FLAG,
329 	    &err_adap);
330 
331 	if (devclass_get_devices(devclass_find("hn"), &devs, &devcnt) == 0) {
332 		for (devcnt = devcnt - 1; devcnt >= 0; devcnt--) {
333 			sc = device_get_softc(devs[devcnt]);
334 
335 			/* Trying to find GUID of Network Device */
336 			hv_dev = sc->hn_dev_obj;
337 
338 			snprintf_hv_guid(buf, sizeof(buf), &hv_dev->device_id);
339 			sprintf(if_name, "%s%d", "hn", device_get_unit(devs[devcnt]));
340 
341 			if (strncmp(buf, (char *)umsg->body.kvp_ip_val.adapter_id, 39) == 0) {
342 				strcpy((char *)umsg->body.kvp_ip_val.adapter_id, if_name);
343 				break;
344 			}
345 		}
346 		free(devs, M_TEMP);
347 	}
348 
349 	/* Address Family , DHCP , SUBNET, Gateway, DNS */
350 	umsg->kvp_hdr.operation = host_ip_msg->operation;
351 	umsg->body.kvp_ip_val.addr_family = host_ip_msg->kvp_ip_val.addr_family;
352 	umsg->body.kvp_ip_val.dhcp_enabled = host_ip_msg->kvp_ip_val.dhcp_enabled;
353 	utf16_to_utf8((char *)umsg->body.kvp_ip_val.sub_net, MAX_IP_ADDR_SIZE,
354 	    (uint16_t *)host_ip_msg->kvp_ip_val.sub_net,
355 	    MAX_IP_ADDR_SIZE,
356 	    UNUSED_FLAG,
357 	    &err_subnet);
358 
359 	utf16_to_utf8((char *)umsg->body.kvp_ip_val.gate_way, MAX_GATEWAY_SIZE,
360 	    (uint16_t *)host_ip_msg->kvp_ip_val.gate_way,
361 	    MAX_GATEWAY_SIZE,
362 	    UNUSED_FLAG,
363 	    &err_gway);
364 
365 	utf16_to_utf8((char *)umsg->body.kvp_ip_val.dns_addr, MAX_IP_ADDR_SIZE,
366 	    (uint16_t *)host_ip_msg->kvp_ip_val.dns_addr,
367 	    MAX_IP_ADDR_SIZE,
368 	    UNUSED_FLAG,
369 	    &err_dns);
370 
371 	return (err_ip | err_subnet | err_gway | err_dns | err_adap);
372 }
373 
374 
375 /*
376  * Prepare a user kvp msg based on host kvp msg (utf16 to utf8)
377  * Ensure utf16_utf8 takes care of the additional string terminating char!!
378  */
379 static void
380 hv_kvp_convert_hostmsg_to_usermsg(struct hv_kvp_msg *hmsg, struct hv_kvp_msg *umsg)
381 {
382 	int utf_err = 0;
383 	uint32_t value_type;
384 	struct hv_kvp_ip_msg *host_ip_msg;
385 
386 	host_ip_msg = (struct hv_kvp_ip_msg*)hmsg;
387 	memset(umsg, 0, sizeof(struct hv_kvp_msg));
388 
389 	umsg->kvp_hdr.operation = hmsg->kvp_hdr.operation;
390 	umsg->kvp_hdr.pool = hmsg->kvp_hdr.pool;
391 
392 	switch (umsg->kvp_hdr.operation) {
393 	case HV_KVP_OP_SET_IP_INFO:
394 		hv_kvp_convert_utf16_ipinfo_to_utf8(host_ip_msg, umsg);
395 		break;
396 
397 	case HV_KVP_OP_GET_IP_INFO:
398 		utf16_to_utf8((char *)umsg->body.kvp_ip_val.adapter_id,
399 		    MAX_ADAPTER_ID_SIZE,
400 		    (uint16_t *)host_ip_msg->kvp_ip_val.adapter_id,
401 		    MAX_ADAPTER_ID_SIZE, 1, &utf_err);
402 
403 		umsg->body.kvp_ip_val.addr_family =
404 		    host_ip_msg->kvp_ip_val.addr_family;
405 		break;
406 
407 	case HV_KVP_OP_SET:
408 		value_type = hmsg->body.kvp_set.data.value_type;
409 
410 		switch (value_type) {
411 		case HV_REG_SZ:
412 			umsg->body.kvp_set.data.value_size =
413 			    utf16_to_utf8(
414 				(char *)umsg->body.kvp_set.data.msg_value.value,
415 				HV_KVP_EXCHANGE_MAX_VALUE_SIZE - 1,
416 				(uint16_t *)hmsg->body.kvp_set.data.msg_value.value,
417 				hmsg->body.kvp_set.data.value_size,
418 				1, &utf_err);
419 			/* utf8 encoding */
420 			umsg->body.kvp_set.data.value_size =
421 			    umsg->body.kvp_set.data.value_size / 2;
422 			break;
423 
424 		case HV_REG_U32:
425 			umsg->body.kvp_set.data.value_size =
426 			    sprintf(umsg->body.kvp_set.data.msg_value.value, "%d",
427 				hmsg->body.kvp_set.data.msg_value.value_u32) + 1;
428 			break;
429 
430 		case HV_REG_U64:
431 			umsg->body.kvp_set.data.value_size =
432 			    sprintf(umsg->body.kvp_set.data.msg_value.value, "%llu",
433 				(unsigned long long)
434 				hmsg->body.kvp_set.data.msg_value.value_u64) + 1;
435 			break;
436 		}
437 
438 		umsg->body.kvp_set.data.key_size =
439 		    utf16_to_utf8(
440 			umsg->body.kvp_set.data.key,
441 			HV_KVP_EXCHANGE_MAX_KEY_SIZE - 1,
442 			(uint16_t *)hmsg->body.kvp_set.data.key,
443 			hmsg->body.kvp_set.data.key_size,
444 			1, &utf_err);
445 
446 		/* utf8 encoding */
447 		umsg->body.kvp_set.data.key_size =
448 		    umsg->body.kvp_set.data.key_size / 2;
449 		break;
450 
451 	case HV_KVP_OP_GET:
452 		umsg->body.kvp_get.data.key_size =
453 		    utf16_to_utf8(umsg->body.kvp_get.data.key,
454 			HV_KVP_EXCHANGE_MAX_KEY_SIZE - 1,
455 			(uint16_t *)hmsg->body.kvp_get.data.key,
456 			hmsg->body.kvp_get.data.key_size,
457 			1, &utf_err);
458 		/* utf8 encoding */
459 		umsg->body.kvp_get.data.key_size =
460 		    umsg->body.kvp_get.data.key_size / 2;
461 		break;
462 
463 	case HV_KVP_OP_DELETE:
464 		umsg->body.kvp_delete.key_size =
465 		    utf16_to_utf8(umsg->body.kvp_delete.key,
466 			HV_KVP_EXCHANGE_MAX_KEY_SIZE - 1,
467 			(uint16_t *)hmsg->body.kvp_delete.key,
468 			hmsg->body.kvp_delete.key_size,
469 			1, &utf_err);
470 		/* utf8 encoding */
471 		umsg->body.kvp_delete.key_size =
472 		    umsg->body.kvp_delete.key_size / 2;
473 		break;
474 
475 	case HV_KVP_OP_ENUMERATE:
476 		umsg->body.kvp_enum_data.index =
477 		    hmsg->body.kvp_enum_data.index;
478 		break;
479 
480 	default:
481 		hv_kvp_log_info("%s: daemon_kvp_msg: Invalid operation : %d\n",
482 		    __func__, umsg->kvp_hdr.operation);
483 	}
484 }
485 
486 
487 /*
488  * Prepare a host kvp msg based on user kvp msg (utf8 to utf16)
489  */
490 static int
491 hv_kvp_convert_usermsg_to_hostmsg(struct hv_kvp_msg *umsg, struct hv_kvp_msg *hmsg)
492 {
493 	int hkey_len = 0, hvalue_len = 0, utf_err = 0;
494 	struct hv_kvp_exchg_msg_value *host_exchg_data;
495 	char *key_name, *value;
496 
497 	struct hv_kvp_ip_msg *host_ip_msg = (struct hv_kvp_ip_msg *)hmsg;
498 
499 	switch (hmsg->kvp_hdr.operation) {
500 	case HV_KVP_OP_GET_IP_INFO:
501 		return (hv_kvp_convert_utf8_ipinfo_to_utf16(umsg, host_ip_msg));
502 
503 	case HV_KVP_OP_SET_IP_INFO:
504 	case HV_KVP_OP_SET:
505 	case HV_KVP_OP_DELETE:
506 		return (KVP_SUCCESS);
507 
508 	case HV_KVP_OP_ENUMERATE:
509 		host_exchg_data = &hmsg->body.kvp_enum_data.data;
510 		key_name = umsg->body.kvp_enum_data.data.key;
511 		hkey_len = utf8_to_utf16((uint16_t *)host_exchg_data->key,
512 				((HV_KVP_EXCHANGE_MAX_KEY_SIZE / 2) - 2),
513 				key_name, strlen(key_name),
514 				1, &utf_err);
515 		/* utf16 encoding */
516 		host_exchg_data->key_size = 2 * (hkey_len + 1);
517 		value = umsg->body.kvp_enum_data.data.msg_value.value;
518 		hvalue_len = utf8_to_utf16(
519 				(uint16_t *)host_exchg_data->msg_value.value,
520 				((HV_KVP_EXCHANGE_MAX_VALUE_SIZE / 2) - 2),
521 				value, strlen(value),
522 				1, &utf_err);
523 		host_exchg_data->value_size = 2 * (hvalue_len + 1);
524 		host_exchg_data->value_type = HV_REG_SZ;
525 
526 		if ((hkey_len < 0) || (hvalue_len < 0))
527 			return (HV_KVP_E_FAIL);
528 
529 		return (KVP_SUCCESS);
530 
531 	case HV_KVP_OP_GET:
532 		host_exchg_data = &hmsg->body.kvp_get.data;
533 		value = umsg->body.kvp_get.data.msg_value.value;
534 		hvalue_len = utf8_to_utf16(
535 				(uint16_t *)host_exchg_data->msg_value.value,
536 				((HV_KVP_EXCHANGE_MAX_VALUE_SIZE / 2) - 2),
537 				value, strlen(value),
538 				1, &utf_err);
539 		/* Convert value size to uft16 */
540 		host_exchg_data->value_size = 2 * (hvalue_len + 1);
541 		/* Use values by string */
542 		host_exchg_data->value_type = HV_REG_SZ;
543 
544 		if ((hkey_len < 0) || (hvalue_len < 0))
545 			return (HV_KVP_E_FAIL);
546 
547 		return (KVP_SUCCESS);
548 
549 	default:
550 		return (HV_KVP_E_FAIL);
551 	}
552 }
553 
554 
555 /*
556  * Send the response back to the host.
557  */
558 static void
559 hv_kvp_respond_host(hv_kvp_sc *sc, int error)
560 {
561 	struct hv_vmbus_icmsg_hdr *hv_icmsg_hdrp;
562 
563 	hv_icmsg_hdrp = (struct hv_vmbus_icmsg_hdr *)
564 	    &sc->rcv_buf[sizeof(struct hv_vmbus_pipe_hdr)];
565 
566 	if (error)
567 		error = HV_KVP_E_FAIL;
568 
569 	hv_icmsg_hdrp->status = error;
570 	hv_icmsg_hdrp->icflags = HV_ICMSGHDRFLAG_TRANSACTION | HV_ICMSGHDRFLAG_RESPONSE;
571 
572 	error = hv_vmbus_channel_send_packet(sc->util_sc.hv_dev->channel,
573 			sc->rcv_buf,
574 			sc->host_msg_len, sc->host_msg_id,
575 			HV_VMBUS_PACKET_TYPE_DATA_IN_BAND, 0);
576 
577 	if (error)
578 		hv_kvp_log_info("%s: hv_kvp_respond_host: sendpacket error:%d\n",
579 			__func__, error);
580 }
581 
582 
583 /*
584  * This is the main kvp kernel process that interacts with both user daemon
585  * and the host
586  */
587 static void
588 hv_kvp_send_msg_to_daemon(hv_kvp_sc *sc)
589 {
590 	struct hv_kvp_msg *hmsg = sc->host_kvp_msg;
591 	struct hv_kvp_msg *umsg = &sc->daemon_kvp_msg;
592 
593 	/* Prepare kvp_msg to be sent to user */
594 	hv_kvp_convert_hostmsg_to_usermsg(hmsg, umsg);
595 
596 	/* Send the msg to user via function deamon_read - setting sema */
597 	sema_post(&sc->dev_sema);
598 
599 	/* We should wake up the daemon, in case it's doing poll() */
600 	selwakeup(&sc->hv_kvp_selinfo);
601 }
602 
603 
604 /*
605  * Function to read the kvp request buffer from host
606  * and interact with daemon
607  */
608 static void
609 hv_kvp_process_request(void *context, int pending)
610 {
611 	uint8_t *kvp_buf;
612 	hv_vmbus_channel *channel;
613 	uint32_t recvlen = 0;
614 	uint64_t requestid;
615 	struct hv_vmbus_icmsg_hdr *icmsghdrp;
616 	int ret = 0;
617 	hv_kvp_sc		*sc;
618 
619 	hv_kvp_log_info("%s: entering hv_kvp_process_request\n", __func__);
620 
621 	sc = (hv_kvp_sc*)context;
622 	kvp_buf = sc->util_sc.receive_buffer;
623 	channel = sc->util_sc.hv_dev->channel;
624 
625 	ret = hv_vmbus_channel_recv_packet(channel, kvp_buf, 2 * PAGE_SIZE,
626 		&recvlen, &requestid);
627 
628 	while ((ret == 0) && (recvlen > 0)) {
629 
630 		icmsghdrp = (struct hv_vmbus_icmsg_hdr *)
631 			&kvp_buf[sizeof(struct hv_vmbus_pipe_hdr)];
632 
633 		hv_kvp_transaction_init(sc, recvlen, requestid, kvp_buf);
634 		if (icmsghdrp->icmsgtype == HV_ICMSGTYPE_NEGOTIATE) {
635 			hv_kvp_negotiate_version(icmsghdrp, NULL, kvp_buf);
636 			hv_kvp_respond_host(sc, ret);
637 
638 			/*
639 			 * It is ok to not acquire the mutex before setting
640 			 * req_in_progress here because negotiation is the
641 			 * first thing that happens and hence there is no
642 			 * chance of a race condition.
643 			 */
644 
645 			sc->req_in_progress = false;
646 			hv_kvp_log_info("%s :version negotiated\n", __func__);
647 
648 		} else {
649 			if (!sc->daemon_busy) {
650 
651 				hv_kvp_log_info("%s: issuing qury to daemon\n", __func__);
652 				mtx_lock(&sc->pending_mutex);
653 				sc->req_timed_out = false;
654 				sc->daemon_busy = true;
655 				mtx_unlock(&sc->pending_mutex);
656 
657 				hv_kvp_send_msg_to_daemon(sc);
658 				hv_kvp_log_info("%s: waiting for daemon\n", __func__);
659 			}
660 
661 			/* Wait 5 seconds for daemon to respond back */
662 			tsleep(sc, 0, "kvpworkitem", 5 * hz);
663 			hv_kvp_log_info("%s: came out of wait\n", __func__);
664 		}
665 
666 		mtx_lock(&sc->pending_mutex);
667 
668 		/* Notice that once req_timed_out is set to true
669 		 * it will remain true until the next request is
670 		 * sent to the daemon. The response from daemon
671 		 * is forwarded to host only when this flag is
672 		 * false.
673 		 */
674 		sc->req_timed_out = true;
675 
676 		/*
677 		 * Cancel request if so need be.
678 		 */
679 		if (hv_kvp_req_in_progress(sc)) {
680 			hv_kvp_log_info("%s: request was still active after wait so failing\n", __func__);
681 			hv_kvp_respond_host(sc, HV_KVP_E_FAIL);
682 			sc->req_in_progress = false;
683 		}
684 
685 		mtx_unlock(&sc->pending_mutex);
686 
687 		/*
688 		 * Try reading next buffer
689 		 */
690 		recvlen = 0;
691 		ret = hv_vmbus_channel_recv_packet(channel, kvp_buf, 2 * PAGE_SIZE,
692 			&recvlen, &requestid);
693 		hv_kvp_log_info("%s: read: context %p, ret =%d, recvlen=%d\n",
694 			__func__, context, ret, recvlen);
695 	}
696 }
697 
698 
699 /*
700  * Callback routine that gets called whenever there is a message from host
701  */
702 static void
703 hv_kvp_callback(void *context)
704 {
705 	hv_kvp_sc *sc = (hv_kvp_sc*)context;
706 	/*
707 	 The first request from host will not be handled until daemon is registered.
708 	 when callback is triggered without a registered daemon, callback just return.
709 	 When a new daemon gets regsitered, this callbcak is trigged from _write op.
710 	*/
711 	if (sc->register_done) {
712 		hv_kvp_log_info("%s: Queuing work item\n", __func__);
713 		taskqueue_enqueue(taskqueue_thread, &sc->task);
714 	}
715 }
716 
717 static int
718 hv_kvp_dev_open(struct cdev *dev, int oflags, int devtype,
719 				struct thread *td)
720 {
721 	hv_kvp_sc *sc = (hv_kvp_sc*)dev->si_drv1;
722 
723 	hv_kvp_log_info("%s: Opened device \"hv_kvp_device\" successfully.\n", __func__);
724 	if (sc->dev_accessed)
725 		return (-EBUSY);
726 
727 	sc->daemon_task = curproc;
728 	sc->dev_accessed = true;
729 	sc->daemon_busy = false;
730 	return (0);
731 }
732 
733 
734 static int
735 hv_kvp_dev_close(struct cdev *dev __unused, int fflag __unused, int devtype __unused,
736 				 struct thread *td __unused)
737 {
738 	hv_kvp_sc *sc = (hv_kvp_sc*)dev->si_drv1;
739 
740 	hv_kvp_log_info("%s: Closing device \"hv_kvp_device\".\n", __func__);
741 	sc->dev_accessed = false;
742 	sc->register_done = false;
743 	return (0);
744 }
745 
746 
747 /*
748  * hv_kvp_daemon read invokes this function
749  * acts as a send to daemon
750  */
751 static int
752 hv_kvp_dev_daemon_read(struct cdev *dev, struct uio *uio, int ioflag __unused)
753 {
754 	size_t amt;
755 	int error = 0;
756 	struct hv_kvp_msg *hv_kvp_dev_buf;
757 	hv_kvp_sc *sc = (hv_kvp_sc*)dev->si_drv1;
758 
759 	/* Check hv_kvp daemon registration status*/
760 	if (!sc->register_done)
761 		return (KVP_ERROR);
762 
763 	sema_wait(&sc->dev_sema);
764 
765 	hv_kvp_dev_buf = malloc(sizeof(*hv_kvp_dev_buf), M_TEMP, M_WAITOK);
766 	memcpy(hv_kvp_dev_buf, &sc->daemon_kvp_msg, sizeof(struct hv_kvp_msg));
767 
768 	amt = MIN(uio->uio_resid, uio->uio_offset >= BUFFERSIZE + 1 ? 0 :
769 		BUFFERSIZE + 1 - uio->uio_offset);
770 
771 	if ((error = uiomove(hv_kvp_dev_buf, amt, uio)) != 0)
772 		hv_kvp_log_info("%s: hv_kvp uiomove read failed!\n", __func__);
773 
774 	free(hv_kvp_dev_buf, M_TEMP);
775 	return (error);
776 }
777 
778 
779 /*
780  * hv_kvp_daemon write invokes this function
781  * acts as a receive from daemon
782  */
783 static int
784 hv_kvp_dev_daemon_write(struct cdev *dev, struct uio *uio, int ioflag __unused)
785 {
786 	size_t amt;
787 	int error = 0;
788 	struct hv_kvp_msg *hv_kvp_dev_buf;
789 	hv_kvp_sc *sc = (hv_kvp_sc*)dev->si_drv1;
790 
791 	uio->uio_offset = 0;
792 	hv_kvp_dev_buf = malloc(sizeof(*hv_kvp_dev_buf), M_TEMP, M_WAITOK);
793 
794 	amt = MIN(uio->uio_resid, BUFFERSIZE);
795 	error = uiomove(hv_kvp_dev_buf, amt, uio);
796 
797 	if (error != 0) {
798 		free(hv_kvp_dev_buf, M_TEMP);
799 		return (error);
800 	}
801 	memcpy(&sc->daemon_kvp_msg, hv_kvp_dev_buf, sizeof(struct hv_kvp_msg));
802 
803 	free(hv_kvp_dev_buf, M_TEMP);
804 	if (sc->register_done == false) {
805 		if (sc->daemon_kvp_msg.kvp_hdr.operation == HV_KVP_OP_REGISTER) {
806 			sc->register_done = true;
807 			hv_kvp_callback(dev->si_drv1);
808 		}
809 		else {
810 			hv_kvp_log_info("%s, KVP Registration Failed\n", __func__);
811 			return (KVP_ERROR);
812 		}
813 	} else {
814 
815 		mtx_lock(&sc->pending_mutex);
816 
817 		if(!sc->req_timed_out) {
818 			struct hv_kvp_msg *hmsg = sc->host_kvp_msg;
819 			struct hv_kvp_msg *umsg = &sc->daemon_kvp_msg;
820 
821 			hv_kvp_convert_usermsg_to_hostmsg(umsg, hmsg);
822 			hv_kvp_respond_host(sc, KVP_SUCCESS);
823 			wakeup(sc);
824 			sc->req_in_progress = false;
825 		}
826 
827 		sc->daemon_busy = false;
828 		mtx_unlock(&sc->pending_mutex);
829 	}
830 
831 	return (error);
832 }
833 
834 
835 /*
836  * hv_kvp_daemon poll invokes this function to check if data is available
837  * for daemon to read.
838  */
839 static int
840 hv_kvp_dev_daemon_poll(struct cdev *dev, int events, struct thread *td)
841 {
842 	int revents = 0;
843 	hv_kvp_sc *sc = (hv_kvp_sc*)dev->si_drv1;
844 
845 	mtx_lock(&sc->pending_mutex);
846 	/*
847 	 * We check global flag daemon_busy for the data availiability for
848 	 * userland to read. Deamon_busy is set to true before driver has data
849 	 * for daemon to read. It is set to false after daemon sends
850 	 * then response back to driver.
851 	 */
852 	if (sc->daemon_busy == true)
853 		revents = POLLIN;
854 	else
855 		selrecord(td, &sc->hv_kvp_selinfo);
856 
857 	mtx_unlock(&sc->pending_mutex);
858 
859 	return (revents);
860 }
861 
862 static int
863 hv_kvp_probe(device_t dev)
864 {
865 	const char *p = vmbus_get_type(dev);
866 
867 	if (resource_disabled("hvkvp", 0))
868 		return ENXIO;
869 
870 	if (!memcmp(p, &service_guid, sizeof(hv_guid))) {
871 		device_set_desc(dev, "Hyper-V KVP Service");
872 		return BUS_PROBE_DEFAULT;
873 	}
874 
875 	return ENXIO;
876 }
877 
878 static int
879 hv_kvp_attach(device_t dev)
880 {
881 	int error;
882 	struct sysctl_oid_list *child;
883 	struct sysctl_ctx_list *ctx;
884 
885 	hv_kvp_sc *sc = (hv_kvp_sc*)device_get_softc(dev);
886 
887 	sc->util_sc.callback = hv_kvp_callback;
888 	sema_init(&sc->dev_sema, 0, "hv_kvp device semaphore");
889 	mtx_init(&sc->pending_mutex, "hv-kvp pending mutex",
890 		NULL, MTX_DEF);
891 
892 	ctx = device_get_sysctl_ctx(dev);
893 	child = SYSCTL_CHILDREN(device_get_sysctl_tree(dev));
894 
895 	SYSCTL_ADD_INT(ctx, child, OID_AUTO, "hv_kvp_log",
896 	    CTLFLAG_RW, &hv_kvp_log, 0, "Hyperv KVP service log level");
897 
898 	TASK_INIT(&sc->task, 0, hv_kvp_process_request, sc);
899 
900 	/* create character device */
901 	error = make_dev_p(MAKEDEV_CHECKNAME | MAKEDEV_WAITOK,
902 			&sc->hv_kvp_dev,
903 			&hv_kvp_cdevsw,
904 			0,
905 			UID_ROOT,
906 			GID_WHEEL,
907 			0640,
908 			"hv_kvp_dev");
909 
910 	if (error != 0)
911 		return (error);
912 	sc->hv_kvp_dev->si_drv1 = sc;
913 
914 	return hv_util_attach(dev);
915 }
916 
917 static int
918 hv_kvp_detach(device_t dev)
919 {
920 	hv_kvp_sc *sc = (hv_kvp_sc*)device_get_softc(dev);
921 
922 	if (sc->daemon_task != NULL) {
923 		PROC_LOCK(sc->daemon_task);
924 		kern_psignal(sc->daemon_task, SIGKILL);
925 		PROC_UNLOCK(sc->daemon_task);
926 	}
927 
928 	destroy_dev(sc->hv_kvp_dev);
929 	return hv_util_detach(dev);
930 }
931 
932 static device_method_t kvp_methods[] = {
933 	/* Device interface */
934 	DEVMETHOD(device_probe, hv_kvp_probe),
935 	DEVMETHOD(device_attach, hv_kvp_attach),
936 	DEVMETHOD(device_detach, hv_kvp_detach),
937 	{ 0, 0 }
938 };
939 
940 static driver_t kvp_driver = { "hvkvp", kvp_methods, sizeof(hv_kvp_sc)};
941 
942 static devclass_t kvp_devclass;
943 
944 DRIVER_MODULE(hv_kvp, vmbus, kvp_driver, kvp_devclass, NULL, NULL);
945 MODULE_VERSION(hv_kvp, 1);
946 MODULE_DEPEND(hv_kvp, vmbus, 1, 1, 1);
947