1/*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (c) 2009-2010 The FreeBSD Foundation
5 * Copyright (c) 2010 Pawel Jakub Dawidek <pjd@FreeBSD.org>
6 * All rights reserved.
7 *
8 * This software was developed by Pawel Jakub Dawidek under sponsorship from
9 * the FreeBSD Foundation.
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 * 1. Redistributions of source code must retain the above copyright
15 *    notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 *    notice, this list of conditions and the following disclaimer in the
18 *    documentation and/or other materials provided with the distribution.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
31 */
32
33#include <sys/param.h>
34#include <sys/time.h>
35#include <sys/bio.h>
36#include <sys/disk.h>
37#include <sys/stat.h>
38
39#include <err.h>
40#include <errno.h>
41#include <fcntl.h>
42#include <libgeom.h>
43#include <pthread.h>
44#include <signal.h>
45#include <stdint.h>
46#include <stdio.h>
47#include <string.h>
48#include <sysexits.h>
49#include <unistd.h>
50
51#include <activemap.h>
52#include <nv.h>
53#include <pjdlog.h>
54
55#include "control.h"
56#include "event.h"
57#include "hast.h"
58#include "hast_proto.h"
59#include "hastd.h"
60#include "hooks.h"
61#include "metadata.h"
62#include "proto.h"
63#include "subr.h"
64#include "synch.h"
65
66struct hio {
67	uint64_t	 hio_seq;
68	int		 hio_error;
69	void		*hio_data;
70	uint8_t		 hio_cmd;
71	uint64_t	 hio_offset;
72	uint64_t	 hio_length;
73	bool		 hio_memsync;
74	TAILQ_ENTRY(hio) hio_next;
75};
76
77static struct hast_resource *gres;
78
79/*
80 * Free list holds unused structures. When free list is empty, we have to wait
81 * until some in-progress requests are freed.
82 */
83static TAILQ_HEAD(, hio) hio_free_list;
84static size_t hio_free_list_size;
85static pthread_mutex_t hio_free_list_lock;
86static pthread_cond_t hio_free_list_cond;
87/*
88 * Disk thread (the one that does I/O requests) takes requests from this list.
89 */
90static TAILQ_HEAD(, hio) hio_disk_list;
91static size_t hio_disk_list_size;
92static pthread_mutex_t hio_disk_list_lock;
93static pthread_cond_t hio_disk_list_cond;
94/*
95 * Thread that sends requests back to primary takes requests from this list.
96 */
97static TAILQ_HEAD(, hio) hio_send_list;
98static size_t hio_send_list_size;
99static pthread_mutex_t hio_send_list_lock;
100static pthread_cond_t hio_send_list_cond;
101
102/*
103 * Maximum number of outstanding I/O requests.
104 */
105#define	HAST_HIO_MAX	256
106
107static void *recv_thread(void *arg);
108static void *disk_thread(void *arg);
109static void *send_thread(void *arg);
110
111#define	QUEUE_INSERT(name, hio)	do {					\
112	mtx_lock(&hio_##name##_list_lock);				\
113	if (TAILQ_EMPTY(&hio_##name##_list))				\
114		cv_broadcast(&hio_##name##_list_cond);			\
115	TAILQ_INSERT_TAIL(&hio_##name##_list, (hio), hio_next);		\
116	hio_##name##_list_size++;					\
117	mtx_unlock(&hio_##name##_list_lock);				\
118} while (0)
119#define	QUEUE_TAKE(name, hio)	do {					\
120	mtx_lock(&hio_##name##_list_lock);				\
121	while (((hio) = TAILQ_FIRST(&hio_##name##_list)) == NULL) {	\
122		cv_wait(&hio_##name##_list_cond,			\
123		    &hio_##name##_list_lock);				\
124	}								\
125	PJDLOG_ASSERT(hio_##name##_list_size != 0);			\
126	hio_##name##_list_size--;					\
127	TAILQ_REMOVE(&hio_##name##_list, (hio), hio_next);		\
128	mtx_unlock(&hio_##name##_list_lock);				\
129} while (0)
130
131static void
132output_status_aux(struct nv *nvout)
133{
134
135	nv_add_uint64(nvout, (uint64_t)hio_free_list_size, "idle_queue_size");
136	nv_add_uint64(nvout, (uint64_t)hio_disk_list_size, "local_queue_size");
137	nv_add_uint64(nvout, (uint64_t)hio_send_list_size, "send_queue_size");
138}
139
140static void
141hio_clear(struct hio *hio)
142{
143
144	hio->hio_seq = 0;
145	hio->hio_error = 0;
146	hio->hio_cmd = HIO_UNDEF;
147	hio->hio_offset = 0;
148	hio->hio_length = 0;
149	hio->hio_memsync = false;
150}
151
152static void
153hio_copy(const struct hio *srchio, struct hio *dsthio)
154{
155
156	/*
157	 * We don't copy hio_error, hio_data and hio_next fields.
158	 */
159
160	dsthio->hio_seq = srchio->hio_seq;
161	dsthio->hio_cmd = srchio->hio_cmd;
162	dsthio->hio_offset = srchio->hio_offset;
163	dsthio->hio_length = srchio->hio_length;
164	dsthio->hio_memsync = srchio->hio_memsync;
165}
166
167static void
168init_environment(void)
169{
170	struct hio *hio;
171	unsigned int ii;
172
173	/*
174	 * Initialize lists, their locks and theirs condition variables.
175	 */
176	TAILQ_INIT(&hio_free_list);
177	mtx_init(&hio_free_list_lock);
178	cv_init(&hio_free_list_cond);
179	TAILQ_INIT(&hio_disk_list);
180	mtx_init(&hio_disk_list_lock);
181	cv_init(&hio_disk_list_cond);
182	TAILQ_INIT(&hio_send_list);
183	mtx_init(&hio_send_list_lock);
184	cv_init(&hio_send_list_cond);
185
186	/*
187	 * Allocate requests pool and initialize requests.
188	 */
189	for (ii = 0; ii < HAST_HIO_MAX; ii++) {
190		hio = malloc(sizeof(*hio));
191		if (hio == NULL) {
192			pjdlog_exitx(EX_TEMPFAIL,
193			    "Unable to allocate memory (%zu bytes) for hio request.",
194			    sizeof(*hio));
195		}
196		hio->hio_data = malloc(MAXPHYS);
197		if (hio->hio_data == NULL) {
198			pjdlog_exitx(EX_TEMPFAIL,
199			    "Unable to allocate memory (%zu bytes) for gctl_data.",
200			    (size_t)MAXPHYS);
201		}
202		hio_clear(hio);
203		TAILQ_INSERT_HEAD(&hio_free_list, hio, hio_next);
204		hio_free_list_size++;
205	}
206}
207
208static void
209init_local(struct hast_resource *res)
210{
211
212	if (metadata_read(res, true) == -1)
213		exit(EX_NOINPUT);
214}
215
216static void
217init_remote(struct hast_resource *res, struct nv *nvin)
218{
219	uint64_t resuid;
220	struct nv *nvout;
221	unsigned char *map;
222	size_t mapsize;
223
224#ifdef notyet
225	/* Setup direction. */
226	if (proto_send(res->hr_remoteout, NULL, 0) == -1)
227		pjdlog_errno(LOG_WARNING, "Unable to set connection direction");
228#endif
229
230	nvout = nv_alloc();
231	nv_add_int64(nvout, (int64_t)res->hr_datasize, "datasize");
232	nv_add_int32(nvout, (int32_t)res->hr_extentsize, "extentsize");
233	resuid = nv_get_uint64(nvin, "resuid");
234	res->hr_primary_localcnt = nv_get_uint64(nvin, "localcnt");
235	res->hr_primary_remotecnt = nv_get_uint64(nvin, "remotecnt");
236	nv_add_uint64(nvout, res->hr_secondary_localcnt, "localcnt");
237	nv_add_uint64(nvout, res->hr_secondary_remotecnt, "remotecnt");
238	mapsize = activemap_calc_ondisk_size(res->hr_local_mediasize -
239	    METADATA_SIZE, res->hr_extentsize, res->hr_local_sectorsize);
240	map = malloc(mapsize);
241	if (map == NULL) {
242		pjdlog_exitx(EX_TEMPFAIL,
243		    "Unable to allocate memory (%zu bytes) for activemap.",
244		    mapsize);
245	}
246	/*
247	 * When we work as primary and secondary is missing we will increase
248	 * localcnt in our metadata. When secondary is connected and synced
249	 * we make localcnt be equal to remotecnt, which means nodes are more
250	 * or less in sync.
251	 * Split-brain condition is when both nodes are not able to communicate
252	 * and are both configured as primary nodes. In turn, they can both
253	 * make incompatible changes to the data and we have to detect that.
254	 * Under split-brain condition we will increase our localcnt on first
255	 * write and remote node will increase its localcnt on first write.
256	 * When we connect we can see that primary's localcnt is greater than
257	 * our remotecnt (primary was modified while we weren't watching) and
258	 * our localcnt is greater than primary's remotecnt (we were modified
259	 * while primary wasn't watching).
260	 * There are many possible combinations which are all gathered below.
261	 * Don't pay too much attention to exact numbers, the more important
262	 * is to compare them. We compare secondary's local with primary's
263	 * remote and secondary's remote with primary's local.
264	 * Note that every case where primary's localcnt is smaller than
265	 * secondary's remotecnt and where secondary's localcnt is smaller than
266	 * primary's remotecnt should be impossible in practise. We will perform
267	 * full synchronization then. Those cases are marked with an asterisk.
268	 * Regular synchronization means that only extents marked as dirty are
269	 * synchronized (regular synchronization).
270	 *
271	 * SECONDARY METADATA PRIMARY METADATA
272	 * local=3 remote=3   local=2 remote=2*  ?! Full sync from secondary.
273	 * local=3 remote=3   local=2 remote=3*  ?! Full sync from primary.
274	 * local=3 remote=3   local=2 remote=4*  ?! Full sync from primary.
275	 * local=3 remote=3   local=3 remote=2   Primary is out-of-date,
276	 *                                       regular sync from secondary.
277	 * local=3 remote=3   local=3 remote=3   Regular sync just in case.
278	 * local=3 remote=3   local=3 remote=4*  ?! Full sync from primary.
279	 * local=3 remote=3   local=4 remote=2   Split-brain condition.
280	 * local=3 remote=3   local=4 remote=3   Secondary out-of-date,
281	 *                                       regular sync from primary.
282	 * local=3 remote=3   local=4 remote=4*  ?! Full sync from primary.
283	 */
284	if (res->hr_resuid == 0) {
285		/*
286		 * Provider is used for the first time. If primary node done no
287		 * writes yet as well (we will find "virgin" argument) then
288		 * there is no need to synchronize anything. If primary node
289		 * done any writes already we have to synchronize everything.
290		 */
291		PJDLOG_ASSERT(res->hr_secondary_localcnt == 0);
292		res->hr_resuid = resuid;
293		if (metadata_write(res) == -1)
294			exit(EX_NOINPUT);
295		if (nv_exists(nvin, "virgin")) {
296			free(map);
297			map = NULL;
298			mapsize = 0;
299		} else {
300			memset(map, 0xff, mapsize);
301		}
302		nv_add_int8(nvout, 1, "virgin");
303		nv_add_uint8(nvout, HAST_SYNCSRC_PRIMARY, "syncsrc");
304	} else if (res->hr_resuid != resuid) {
305		char errmsg[256];
306
307		free(map);
308		(void)snprintf(errmsg, sizeof(errmsg),
309		    "Resource unique ID mismatch (primary=%ju, secondary=%ju).",
310		    (uintmax_t)resuid, (uintmax_t)res->hr_resuid);
311		pjdlog_error("%s", errmsg);
312		nv_add_string(nvout, errmsg, "errmsg");
313		if (hast_proto_send(res, res->hr_remotein, nvout,
314		    NULL, 0) == -1) {
315			pjdlog_exit(EX_TEMPFAIL,
316			    "Unable to send response to %s",
317			    res->hr_remoteaddr);
318		}
319		nv_free(nvout);
320		exit(EX_CONFIG);
321	} else if (
322	    /* Is primary out-of-date? */
323	    (res->hr_secondary_localcnt > res->hr_primary_remotecnt &&
324	     res->hr_secondary_remotecnt == res->hr_primary_localcnt) ||
325	    /* Are the nodes more or less in sync? */
326	    (res->hr_secondary_localcnt == res->hr_primary_remotecnt &&
327	     res->hr_secondary_remotecnt == res->hr_primary_localcnt) ||
328	    /* Is secondary out-of-date? */
329	    (res->hr_secondary_localcnt == res->hr_primary_remotecnt &&
330	     res->hr_secondary_remotecnt < res->hr_primary_localcnt)) {
331		/*
332		 * Nodes are more or less in sync or one of the nodes is
333		 * out-of-date.
334		 * It doesn't matter at this point which one, we just have to
335		 * send out local bitmap to the remote node.
336		 */
337		if (pread(res->hr_localfd, map, mapsize, METADATA_SIZE) !=
338		    (ssize_t)mapsize) {
339			pjdlog_exit(LOG_ERR, "Unable to read activemap");
340		}
341		if (res->hr_secondary_localcnt > res->hr_primary_remotecnt &&
342		     res->hr_secondary_remotecnt == res->hr_primary_localcnt) {
343			/* Primary is out-of-date, sync from secondary. */
344			nv_add_uint8(nvout, HAST_SYNCSRC_SECONDARY, "syncsrc");
345		} else {
346			/*
347			 * Secondary is out-of-date or counts match.
348			 * Sync from primary.
349			 */
350			nv_add_uint8(nvout, HAST_SYNCSRC_PRIMARY, "syncsrc");
351		}
352	} else if (res->hr_secondary_localcnt > res->hr_primary_remotecnt &&
353	     res->hr_primary_localcnt > res->hr_secondary_remotecnt) {
354		/*
355		 * Not good, we have split-brain condition.
356		 */
357		free(map);
358		pjdlog_error("Split-brain detected, exiting.");
359		nv_add_string(nvout, "Split-brain condition!", "errmsg");
360		if (hast_proto_send(res, res->hr_remotein, nvout,
361		    NULL, 0) == -1) {
362			pjdlog_exit(EX_TEMPFAIL,
363			    "Unable to send response to %s",
364			    res->hr_remoteaddr);
365		}
366		nv_free(nvout);
367		/* Exit on split-brain. */
368		event_send(res, EVENT_SPLITBRAIN);
369		exit(EX_CONFIG);
370	} else /* if (res->hr_secondary_localcnt < res->hr_primary_remotecnt ||
371	    res->hr_primary_localcnt < res->hr_secondary_remotecnt) */ {
372		/*
373		 * This should never happen in practise, but we will perform
374		 * full synchronization.
375		 */
376		PJDLOG_ASSERT(res->hr_secondary_localcnt < res->hr_primary_remotecnt ||
377		    res->hr_primary_localcnt < res->hr_secondary_remotecnt);
378		mapsize = activemap_calc_ondisk_size(res->hr_local_mediasize -
379		    METADATA_SIZE, res->hr_extentsize,
380		    res->hr_local_sectorsize);
381		memset(map, 0xff, mapsize);
382		if (res->hr_secondary_localcnt > res->hr_primary_remotecnt) {
383			/* In this one of five cases sync from secondary. */
384			nv_add_uint8(nvout, HAST_SYNCSRC_SECONDARY, "syncsrc");
385		} else {
386			/* For the rest four cases sync from primary. */
387			nv_add_uint8(nvout, HAST_SYNCSRC_PRIMARY, "syncsrc");
388		}
389		pjdlog_warning("This should never happen, asking for full synchronization (primary(local=%ju, remote=%ju), secondary(local=%ju, remote=%ju)).",
390		    (uintmax_t)res->hr_primary_localcnt,
391		    (uintmax_t)res->hr_primary_remotecnt,
392		    (uintmax_t)res->hr_secondary_localcnt,
393		    (uintmax_t)res->hr_secondary_remotecnt);
394	}
395	nv_add_uint32(nvout, (uint32_t)mapsize, "mapsize");
396	if (hast_proto_send(res, res->hr_remotein, nvout, map, mapsize) == -1) {
397		pjdlog_exit(EX_TEMPFAIL, "Unable to send activemap to %s",
398		    res->hr_remoteaddr);
399	}
400	if (map != NULL)
401		free(map);
402	nv_free(nvout);
403#ifdef notyet
404	/* Setup direction. */
405	if (proto_recv(res->hr_remotein, NULL, 0) == -1)
406		pjdlog_errno(LOG_WARNING, "Unable to set connection direction");
407#endif
408}
409
410void
411hastd_secondary(struct hast_resource *res, struct nv *nvin)
412{
413	sigset_t mask;
414	pthread_t td;
415	pid_t pid;
416	int error, mode, debuglevel;
417
418	/*
419	 * Create communication channel between parent and child.
420	 */
421	if (proto_client(NULL, "socketpair://", &res->hr_ctrl) == -1) {
422		KEEP_ERRNO((void)pidfile_remove(pfh));
423		pjdlog_exit(EX_OSERR,
424		    "Unable to create control sockets between parent and child");
425	}
426	/*
427	 * Create communication channel between child and parent.
428	 */
429	if (proto_client(NULL, "socketpair://", &res->hr_event) == -1) {
430		KEEP_ERRNO((void)pidfile_remove(pfh));
431		pjdlog_exit(EX_OSERR,
432		    "Unable to create event sockets between child and parent");
433	}
434
435	pid = fork();
436	if (pid == -1) {
437		KEEP_ERRNO((void)pidfile_remove(pfh));
438		pjdlog_exit(EX_OSERR, "Unable to fork");
439	}
440
441	if (pid > 0) {
442		/* This is parent. */
443		proto_close(res->hr_remotein);
444		res->hr_remotein = NULL;
445		proto_close(res->hr_remoteout);
446		res->hr_remoteout = NULL;
447		/* Declare that we are receiver. */
448		proto_recv(res->hr_event, NULL, 0);
449		/* Declare that we are sender. */
450		proto_send(res->hr_ctrl, NULL, 0);
451		res->hr_workerpid = pid;
452		return;
453	}
454
455	gres = res;
456	res->output_status_aux = output_status_aux;
457	mode = pjdlog_mode_get();
458	debuglevel = pjdlog_debug_get();
459
460	/* Declare that we are sender. */
461	proto_send(res->hr_event, NULL, 0);
462	/* Declare that we are receiver. */
463	proto_recv(res->hr_ctrl, NULL, 0);
464	descriptors_cleanup(res);
465
466	descriptors_assert(res, mode);
467
468	pjdlog_init(mode);
469	pjdlog_debug_set(debuglevel);
470	pjdlog_prefix_set("[%s] (%s) ", res->hr_name, role2str(res->hr_role));
471	setproctitle("%s (%s)", res->hr_name, role2str(res->hr_role));
472
473	PJDLOG_VERIFY(sigemptyset(&mask) == 0);
474	PJDLOG_VERIFY(sigprocmask(SIG_SETMASK, &mask, NULL) == 0);
475
476	/* Error in setting timeout is not critical, but why should it fail? */
477	if (proto_timeout(res->hr_remotein, 2 * HAST_KEEPALIVE) == -1)
478		pjdlog_errno(LOG_WARNING, "Unable to set connection timeout");
479	if (proto_timeout(res->hr_remoteout, res->hr_timeout) == -1)
480		pjdlog_errno(LOG_WARNING, "Unable to set connection timeout");
481
482	init_local(res);
483	init_environment();
484
485	if (drop_privs(res) != 0)
486		exit(EX_CONFIG);
487	pjdlog_info("Privileges successfully dropped.");
488
489	/*
490	 * Create the control thread before sending any event to the parent,
491	 * as we can deadlock when parent sends control request to worker,
492	 * but worker has no control thread started yet, so parent waits.
493	 * In the meantime worker sends an event to the parent, but parent
494	 * is unable to handle the event, because it waits for control
495	 * request response.
496	 */
497	error = pthread_create(&td, NULL, ctrl_thread, res);
498	PJDLOG_ASSERT(error == 0);
499
500	init_remote(res, nvin);
501	event_send(res, EVENT_CONNECT);
502
503	error = pthread_create(&td, NULL, recv_thread, res);
504	PJDLOG_ASSERT(error == 0);
505	error = pthread_create(&td, NULL, disk_thread, res);
506	PJDLOG_ASSERT(error == 0);
507	(void)send_thread(res);
508}
509
510static void
511reqlog(int loglevel, int debuglevel, int error, struct hio *hio,
512    const char *fmt, ...)
513{
514	char msg[1024];
515	va_list ap;
516	int len;
517
518	va_start(ap, fmt);
519	len = vsnprintf(msg, sizeof(msg), fmt, ap);
520	va_end(ap);
521	if ((size_t)len < sizeof(msg)) {
522		switch (hio->hio_cmd) {
523		case HIO_READ:
524			(void)snprintf(msg + len, sizeof(msg) - len,
525			    "READ(%ju, %ju).", (uintmax_t)hio->hio_offset,
526			    (uintmax_t)hio->hio_length);
527			break;
528		case HIO_DELETE:
529			(void)snprintf(msg + len, sizeof(msg) - len,
530			    "DELETE(%ju, %ju).", (uintmax_t)hio->hio_offset,
531			    (uintmax_t)hio->hio_length);
532			break;
533		case HIO_FLUSH:
534			(void)snprintf(msg + len, sizeof(msg) - len, "FLUSH.");
535			break;
536		case HIO_WRITE:
537			(void)snprintf(msg + len, sizeof(msg) - len,
538			    "WRITE(%ju, %ju).", (uintmax_t)hio->hio_offset,
539			    (uintmax_t)hio->hio_length);
540			break;
541		case HIO_KEEPALIVE:
542			(void)snprintf(msg + len, sizeof(msg) - len, "KEEPALIVE.");
543			break;
544		default:
545			(void)snprintf(msg + len, sizeof(msg) - len,
546			    "UNKNOWN(%u).", (unsigned int)hio->hio_cmd);
547			break;
548		}
549	}
550	pjdlog_common(loglevel, debuglevel, error, "%s", msg);
551}
552
553static int
554requnpack(struct hast_resource *res, struct hio *hio, struct nv *nv)
555{
556
557	hio->hio_cmd = nv_get_uint8(nv, "cmd");
558	if (hio->hio_cmd == 0) {
559		pjdlog_error("Header contains no 'cmd' field.");
560		hio->hio_error = EINVAL;
561		goto end;
562	}
563	if (hio->hio_cmd != HIO_KEEPALIVE) {
564		hio->hio_seq = nv_get_uint64(nv, "seq");
565		if (hio->hio_seq == 0) {
566			pjdlog_error("Header contains no 'seq' field.");
567			hio->hio_error = EINVAL;
568			goto end;
569		}
570	}
571	switch (hio->hio_cmd) {
572	case HIO_FLUSH:
573	case HIO_KEEPALIVE:
574		break;
575	case HIO_WRITE:
576		hio->hio_memsync = nv_exists(nv, "memsync");
577		/* FALLTHROUGH */
578	case HIO_READ:
579	case HIO_DELETE:
580		hio->hio_offset = nv_get_uint64(nv, "offset");
581		if (nv_error(nv) != 0) {
582			pjdlog_error("Header is missing 'offset' field.");
583			hio->hio_error = EINVAL;
584			goto end;
585		}
586		hio->hio_length = nv_get_uint64(nv, "length");
587		if (nv_error(nv) != 0) {
588			pjdlog_error("Header is missing 'length' field.");
589			hio->hio_error = EINVAL;
590			goto end;
591		}
592		if (hio->hio_length == 0) {
593			pjdlog_error("Data length is zero.");
594			hio->hio_error = EINVAL;
595			goto end;
596		}
597		if (hio->hio_cmd != HIO_DELETE && hio->hio_length > MAXPHYS) {
598			pjdlog_error("Data length is too large (%ju > %ju).",
599			    (uintmax_t)hio->hio_length, (uintmax_t)MAXPHYS);
600			hio->hio_error = EINVAL;
601			goto end;
602		}
603		if ((hio->hio_offset % res->hr_local_sectorsize) != 0) {
604			pjdlog_error("Offset %ju is not multiple of sector size.",
605			    (uintmax_t)hio->hio_offset);
606			hio->hio_error = EINVAL;
607			goto end;
608		}
609		if ((hio->hio_length % res->hr_local_sectorsize) != 0) {
610			pjdlog_error("Length %ju is not multiple of sector size.",
611			    (uintmax_t)hio->hio_length);
612			hio->hio_error = EINVAL;
613			goto end;
614		}
615		if (hio->hio_offset + hio->hio_length >
616		    (uint64_t)res->hr_datasize) {
617			pjdlog_error("Data offset is too large (%ju > %ju).",
618			    (uintmax_t)(hio->hio_offset + hio->hio_length),
619			    (uintmax_t)res->hr_datasize);
620			hio->hio_error = EINVAL;
621			goto end;
622		}
623		break;
624	default:
625		pjdlog_error("Header contains invalid 'cmd' (%hhu).",
626		    hio->hio_cmd);
627		hio->hio_error = EINVAL;
628		goto end;
629	}
630	hio->hio_error = 0;
631end:
632	return (hio->hio_error);
633}
634
635static __dead2 void
636secondary_exit(int exitcode, const char *fmt, ...)
637{
638	va_list ap;
639
640	PJDLOG_ASSERT(exitcode != EX_OK);
641	va_start(ap, fmt);
642	pjdlogv_errno(LOG_ERR, fmt, ap);
643	va_end(ap);
644	event_send(gres, EVENT_DISCONNECT);
645	exit(exitcode);
646}
647
648/*
649 * Thread receives requests from the primary node.
650 */
651static void *
652recv_thread(void *arg)
653{
654	struct hast_resource *res = arg;
655	struct hio *hio, *mshio;
656	struct nv *nv;
657
658	for (;;) {
659		pjdlog_debug(2, "recv: Taking free request.");
660		QUEUE_TAKE(free, hio);
661		pjdlog_debug(2, "recv: (%p) Got request.", hio);
662		if (hast_proto_recv_hdr(res->hr_remotein, &nv) == -1) {
663			secondary_exit(EX_TEMPFAIL,
664			    "Unable to receive request header");
665		}
666		if (requnpack(res, hio, nv) != 0) {
667			nv_free(nv);
668			pjdlog_debug(2,
669			    "recv: (%p) Moving request to the send queue.",
670			    hio);
671			QUEUE_INSERT(send, hio);
672			continue;
673		}
674		switch (hio->hio_cmd) {
675		case HIO_READ:
676			res->hr_stat_read++;
677			break;
678		case HIO_WRITE:
679			res->hr_stat_write++;
680			break;
681		case HIO_DELETE:
682			res->hr_stat_delete++;
683			break;
684		case HIO_FLUSH:
685			res->hr_stat_flush++;
686			break;
687		case HIO_KEEPALIVE:
688			break;
689		default:
690			PJDLOG_ABORT("Unexpected command (cmd=%hhu).",
691			    hio->hio_cmd);
692		}
693		reqlog(LOG_DEBUG, 2, -1, hio,
694		    "recv: (%p) Got request header: ", hio);
695		if (hio->hio_cmd == HIO_KEEPALIVE) {
696			nv_free(nv);
697			pjdlog_debug(2,
698			    "recv: (%p) Moving request to the free queue.",
699			    hio);
700			hio_clear(hio);
701			QUEUE_INSERT(free, hio);
702			continue;
703		} else if (hio->hio_cmd == HIO_WRITE) {
704			if (hast_proto_recv_data(res, res->hr_remotein, nv,
705			    hio->hio_data, MAXPHYS) == -1) {
706				secondary_exit(EX_TEMPFAIL,
707				    "Unable to receive request data");
708			}
709			if (hio->hio_memsync) {
710				/*
711				 * For memsync requests we expect two replies.
712				 * Clone the hio so we can handle both of them.
713				 */
714				pjdlog_debug(2, "recv: Taking free request.");
715				QUEUE_TAKE(free, mshio);
716				pjdlog_debug(2, "recv: (%p) Got request.",
717				    mshio);
718				hio_copy(hio, mshio);
719				mshio->hio_error = 0;
720				/*
721				 * We want to keep 'memsync' tag only on the
722				 * request going onto send queue (mshio).
723				 */
724				hio->hio_memsync = false;
725				pjdlog_debug(2,
726				    "recv: (%p) Moving memsync request to the send queue.",
727				    mshio);
728				QUEUE_INSERT(send, mshio);
729			}
730		}
731		nv_free(nv);
732		pjdlog_debug(2, "recv: (%p) Moving request to the disk queue.",
733		    hio);
734		QUEUE_INSERT(disk, hio);
735	}
736	/* NOTREACHED */
737	return (NULL);
738}
739
740/*
741 * Thread reads from or writes to local component and also handles DELETE and
742 * FLUSH requests.
743 */
744static void *
745disk_thread(void *arg)
746{
747	struct hast_resource *res = arg;
748	struct hio *hio;
749	ssize_t ret;
750	bool clear_activemap, logerror;
751
752	clear_activemap = true;
753
754	for (;;) {
755		pjdlog_debug(2, "disk: Taking request.");
756		QUEUE_TAKE(disk, hio);
757		while (clear_activemap) {
758			unsigned char *map;
759			size_t mapsize;
760
761			/*
762			 * When first request is received, it means that primary
763			 * already received our activemap, merged it and stored
764			 * locally. We can now safely clear our activemap.
765			 */
766			mapsize =
767			    activemap_calc_ondisk_size(res->hr_local_mediasize -
768			    METADATA_SIZE, res->hr_extentsize,
769			    res->hr_local_sectorsize);
770			map = calloc(1, mapsize);
771			if (map == NULL) {
772				pjdlog_warning("Unable to allocate memory to clear local activemap.");
773				break;
774			}
775			if (pwrite(res->hr_localfd, map, mapsize,
776			    METADATA_SIZE) != (ssize_t)mapsize) {
777				pjdlog_errno(LOG_WARNING,
778				    "Unable to store cleared activemap");
779				free(map);
780				res->hr_stat_activemap_write_error++;
781				break;
782			}
783			free(map);
784			clear_activemap = false;
785			pjdlog_debug(1, "Local activemap cleared.");
786			break;
787		}
788		reqlog(LOG_DEBUG, 2, -1, hio, "disk: (%p) Got request: ", hio);
789		logerror = true;
790		/* Handle the actual request. */
791		switch (hio->hio_cmd) {
792		case HIO_READ:
793			ret = pread(res->hr_localfd, hio->hio_data,
794			    hio->hio_length,
795			    hio->hio_offset + res->hr_localoff);
796			if (ret == -1)
797				hio->hio_error = errno;
798			else if (ret != (int64_t)hio->hio_length)
799				hio->hio_error = EIO;
800			else
801				hio->hio_error = 0;
802			break;
803		case HIO_WRITE:
804			ret = pwrite(res->hr_localfd, hio->hio_data,
805			    hio->hio_length,
806			    hio->hio_offset + res->hr_localoff);
807			if (ret == -1)
808				hio->hio_error = errno;
809			else if (ret != (int64_t)hio->hio_length)
810				hio->hio_error = EIO;
811			else
812				hio->hio_error = 0;
813			break;
814		case HIO_DELETE:
815			ret = g_delete(res->hr_localfd,
816			    hio->hio_offset + res->hr_localoff,
817			    hio->hio_length);
818			if (ret == -1)
819				hio->hio_error = errno;
820			else
821				hio->hio_error = 0;
822			break;
823		case HIO_FLUSH:
824			if (!res->hr_localflush) {
825				ret = -1;
826				hio->hio_error = EOPNOTSUPP;
827				logerror = false;
828				break;
829			}
830			ret = g_flush(res->hr_localfd);
831			if (ret == -1) {
832				if (errno == EOPNOTSUPP)
833					res->hr_localflush = false;
834				hio->hio_error = errno;
835			} else {
836				hio->hio_error = 0;
837			}
838			break;
839		default:
840			PJDLOG_ABORT("Unexpected command (cmd=%hhu).",
841			    hio->hio_cmd);
842		}
843		if (logerror && hio->hio_error != 0) {
844			reqlog(LOG_ERR, 0, hio->hio_error, hio,
845			    "Request failed: ");
846		}
847		pjdlog_debug(2, "disk: (%p) Moving request to the send queue.",
848		    hio);
849		QUEUE_INSERT(send, hio);
850	}
851	/* NOTREACHED */
852	return (NULL);
853}
854
855/*
856 * Thread sends requests back to primary node.
857 */
858static void *
859send_thread(void *arg)
860{
861	struct hast_resource *res = arg;
862	struct nv *nvout;
863	struct hio *hio;
864	void *data;
865	size_t length;
866
867	for (;;) {
868		pjdlog_debug(2, "send: Taking request.");
869		QUEUE_TAKE(send, hio);
870		reqlog(LOG_DEBUG, 2, -1, hio, "send: (%p) Got request: ", hio);
871		nvout = nv_alloc();
872		/* Copy sequence number. */
873		nv_add_uint64(nvout, hio->hio_seq, "seq");
874		if (hio->hio_memsync) {
875			PJDLOG_ASSERT(hio->hio_cmd == HIO_WRITE);
876			nv_add_int8(nvout, 1, "received");
877		}
878		switch (hio->hio_cmd) {
879		case HIO_READ:
880			if (hio->hio_error == 0) {
881				data = hio->hio_data;
882				length = hio->hio_length;
883				break;
884			}
885			/*
886			 * We send no data in case of an error.
887			 */
888			/* FALLTHROUGH */
889		case HIO_DELETE:
890		case HIO_FLUSH:
891		case HIO_WRITE:
892			data = NULL;
893			length = 0;
894			break;
895		default:
896			PJDLOG_ABORT("Unexpected command (cmd=%hhu).",
897			    hio->hio_cmd);
898		}
899		if (hio->hio_error != 0) {
900			switch (hio->hio_cmd) {
901			case HIO_READ:
902				res->hr_stat_read_error++;
903				break;
904			case HIO_WRITE:
905				res->hr_stat_write_error++;
906				break;
907			case HIO_DELETE:
908				res->hr_stat_delete_error++;
909				break;
910			case HIO_FLUSH:
911				res->hr_stat_flush_error++;
912				break;
913			}
914			nv_add_int16(nvout, hio->hio_error, "error");
915		}
916		if (hast_proto_send(res, res->hr_remoteout, nvout, data,
917		    length) == -1) {
918			secondary_exit(EX_TEMPFAIL, "Unable to send reply");
919		}
920		nv_free(nvout);
921		pjdlog_debug(2, "send: (%p) Moving request to the free queue.",
922		    hio);
923		hio_clear(hio);
924		QUEUE_INSERT(free, hio);
925	}
926	/* NOTREACHED */
927	return (NULL);
928}
929