xref: /openbmc/qemu/net/colo-compare.c (revision 795c40b8)
1 /*
2  * COarse-grain LOck-stepping Virtual Machines for Non-stop Service (COLO)
3  * (a.k.a. Fault Tolerance or Continuous Replication)
4  *
5  * Copyright (c) 2016 HUAWEI TECHNOLOGIES CO., LTD.
6  * Copyright (c) 2016 FUJITSU LIMITED
7  * Copyright (c) 2016 Intel Corporation
8  *
9  * Author: Zhang Chen <zhangchen.fnst@cn.fujitsu.com>
10  *
11  * This work is licensed under the terms of the GNU GPL, version 2 or
12  * later.  See the COPYING file in the top-level directory.
13  */
14 
15 #include "qemu/osdep.h"
16 #include "qemu/error-report.h"
17 #include "trace.h"
18 #include "qemu-common.h"
19 #include "qapi/qmp/qerror.h"
20 #include "qapi/error.h"
21 #include "net/net.h"
22 #include "net/eth.h"
23 #include "qom/object_interfaces.h"
24 #include "qemu/iov.h"
25 #include "qom/object.h"
26 #include "qemu/typedefs.h"
27 #include "net/queue.h"
28 #include "sysemu/char.h"
29 #include "qemu/sockets.h"
30 #include "qapi-visit.h"
31 #include "net/colo.h"
32 
33 #define TYPE_COLO_COMPARE "colo-compare"
34 #define COLO_COMPARE(obj) \
35     OBJECT_CHECK(CompareState, (obj), TYPE_COLO_COMPARE)
36 
37 #define COMPARE_READ_LEN_MAX NET_BUFSIZE
38 #define MAX_QUEUE_SIZE 1024
39 
40 /* TODO: Should be configurable */
41 #define REGULAR_PACKET_CHECK_MS 3000
42 
43 /*
44   + CompareState ++
45   |               |
46   +---------------+   +---------------+         +---------------+
47   |conn list      +--->conn           +--------->conn           |
48   +---------------+   +---------------+         +---------------+
49   |               |     |           |             |          |
50   +---------------+ +---v----+  +---v----+    +---v----+ +---v----+
51                     |primary |  |secondary    |primary | |secondary
52                     |packet  |  |packet  +    |packet  | |packet  +
53                     +--------+  +--------+    +--------+ +--------+
54                         |           |             |          |
55                     +---v----+  +---v----+    +---v----+ +---v----+
56                     |primary |  |secondary    |primary | |secondary
57                     |packet  |  |packet  +    |packet  | |packet  +
58                     +--------+  +--------+    +--------+ +--------+
59                         |           |             |          |
60                     +---v----+  +---v----+    +---v----+ +---v----+
61                     |primary |  |secondary    |primary | |secondary
62                     |packet  |  |packet  +    |packet  | |packet  +
63                     +--------+  +--------+    +--------+ +--------+
64 */
65 typedef struct CompareState {
66     Object parent;
67 
68     char *pri_indev;
69     char *sec_indev;
70     char *outdev;
71     CharBackend chr_pri_in;
72     CharBackend chr_sec_in;
73     CharBackend chr_out;
74     SocketReadState pri_rs;
75     SocketReadState sec_rs;
76 
77     /* connection list: the connections belonged to this NIC could be found
78      * in this list.
79      * element type: Connection
80      */
81     GQueue conn_list;
82     /* hashtable to save connection */
83     GHashTable *connection_track_table;
84     /* compare thread, a thread for each NIC */
85     QemuThread thread;
86 
87     GMainContext *worker_context;
88     GMainLoop *compare_loop;
89 } CompareState;
90 
91 typedef struct CompareClass {
92     ObjectClass parent_class;
93 } CompareClass;
94 
95 enum {
96     PRIMARY_IN = 0,
97     SECONDARY_IN,
98 };
99 
100 static int compare_chr_send(CharBackend *out,
101                             const uint8_t *buf,
102                             uint32_t size);
103 
104 static gint seq_sorter(Packet *a, Packet *b, gpointer data)
105 {
106     struct tcphdr *atcp, *btcp;
107 
108     atcp = (struct tcphdr *)(a->transport_header);
109     btcp = (struct tcphdr *)(b->transport_header);
110     return ntohl(atcp->th_seq) - ntohl(btcp->th_seq);
111 }
112 
113 /*
114  * Return 0 on success, if return -1 means the pkt
115  * is unsupported(arp and ipv6) and will be sent later
116  */
117 static int packet_enqueue(CompareState *s, int mode)
118 {
119     ConnectionKey key;
120     Packet *pkt = NULL;
121     Connection *conn;
122 
123     if (mode == PRIMARY_IN) {
124         pkt = packet_new(s->pri_rs.buf, s->pri_rs.packet_len);
125     } else {
126         pkt = packet_new(s->sec_rs.buf, s->sec_rs.packet_len);
127     }
128 
129     if (parse_packet_early(pkt)) {
130         packet_destroy(pkt, NULL);
131         pkt = NULL;
132         return -1;
133     }
134     fill_connection_key(pkt, &key);
135 
136     conn = connection_get(s->connection_track_table,
137                           &key,
138                           &s->conn_list);
139 
140     if (!conn->processing) {
141         g_queue_push_tail(&s->conn_list, conn);
142         conn->processing = true;
143     }
144 
145     if (mode == PRIMARY_IN) {
146         if (g_queue_get_length(&conn->primary_list) <=
147                                MAX_QUEUE_SIZE) {
148             g_queue_push_tail(&conn->primary_list, pkt);
149             if (conn->ip_proto == IPPROTO_TCP) {
150                 g_queue_sort(&conn->primary_list,
151                              (GCompareDataFunc)seq_sorter,
152                              NULL);
153             }
154         } else {
155             error_report("colo compare primary queue size too big,"
156                          "drop packet");
157         }
158     } else {
159         if (g_queue_get_length(&conn->secondary_list) <=
160                                MAX_QUEUE_SIZE) {
161             g_queue_push_tail(&conn->secondary_list, pkt);
162             if (conn->ip_proto == IPPROTO_TCP) {
163                 g_queue_sort(&conn->secondary_list,
164                              (GCompareDataFunc)seq_sorter,
165                              NULL);
166             }
167         } else {
168             error_report("colo compare secondary queue size too big,"
169                          "drop packet");
170         }
171     }
172 
173     return 0;
174 }
175 
176 /*
177  * The IP packets sent by primary and secondary
178  * will be compared in here
179  * TODO support ip fragment, Out-Of-Order
180  * return:    0  means packet same
181  *            > 0 || < 0 means packet different
182  */
183 static int colo_packet_compare_common(Packet *ppkt, Packet *spkt, int offset)
184 {
185     if (trace_event_get_state(TRACE_COLO_COMPARE_MISCOMPARE)) {
186         char pri_ip_src[20], pri_ip_dst[20], sec_ip_src[20], sec_ip_dst[20];
187 
188         strcpy(pri_ip_src, inet_ntoa(ppkt->ip->ip_src));
189         strcpy(pri_ip_dst, inet_ntoa(ppkt->ip->ip_dst));
190         strcpy(sec_ip_src, inet_ntoa(spkt->ip->ip_src));
191         strcpy(sec_ip_dst, inet_ntoa(spkt->ip->ip_dst));
192 
193         trace_colo_compare_ip_info(ppkt->size, pri_ip_src,
194                                    pri_ip_dst, spkt->size,
195                                    sec_ip_src, sec_ip_dst);
196     }
197 
198     if (ppkt->size == spkt->size) {
199         return memcmp(ppkt->data + offset, spkt->data + offset,
200                       spkt->size - offset);
201     } else {
202         trace_colo_compare_main("Net packet size are not the same");
203         return -1;
204     }
205 }
206 
207 /*
208  * Called from the compare thread on the primary
209  * for compare tcp packet
210  * compare_tcp copied from Dr. David Alan Gilbert's branch
211  */
212 static int colo_packet_compare_tcp(Packet *spkt, Packet *ppkt)
213 {
214     struct tcphdr *ptcp, *stcp;
215     int res;
216 
217     trace_colo_compare_main("compare tcp");
218 
219     ptcp = (struct tcphdr *)ppkt->transport_header;
220     stcp = (struct tcphdr *)spkt->transport_header;
221 
222     /*
223      * The 'identification' field in the IP header is *very* random
224      * it almost never matches.  Fudge this by ignoring differences in
225      * unfragmented packets; they'll normally sort themselves out if different
226      * anyway, and it should recover at the TCP level.
227      * An alternative would be to get both the primary and secondary to rewrite
228      * somehow; but that would need some sync traffic to sync the state
229      */
230     if (ntohs(ppkt->ip->ip_off) & IP_DF) {
231         spkt->ip->ip_id = ppkt->ip->ip_id;
232         /* and the sum will be different if the IDs were different */
233         spkt->ip->ip_sum = ppkt->ip->ip_sum;
234     }
235 
236     /*
237      * Check tcp header length for tcp option field.
238      * th_off > 5 means this tcp packet have options field.
239      * The tcp options maybe always different.
240      * for example:
241      * From RFC 7323.
242      * TCP Timestamps option (TSopt):
243      * Kind: 8
244      *
245      * Length: 10 bytes
246      *
247      *    +-------+-------+---------------------+---------------------+
248      *    |Kind=8 |  10   |   TS Value (TSval)  |TS Echo Reply (TSecr)|
249      *    +-------+-------+---------------------+---------------------+
250      *       1       1              4                     4
251      *
252      * In this case the primary guest's timestamp always different with
253      * the secondary guest's timestamp. COLO just focus on payload,
254      * so we just need skip this field.
255      */
256     if (ptcp->th_off > 5) {
257         ptrdiff_t tcp_offset;
258         tcp_offset = ppkt->transport_header - (uint8_t *)ppkt->data
259                      + (ptcp->th_off * 4);
260         res = colo_packet_compare_common(ppkt, spkt, tcp_offset);
261     } else if (ptcp->th_sum == stcp->th_sum) {
262         res = colo_packet_compare_common(ppkt, spkt, ETH_HLEN);
263     } else {
264         res = -1;
265     }
266 
267     if (res != 0 && trace_event_get_state(TRACE_COLO_COMPARE_MISCOMPARE)) {
268         trace_colo_compare_pkt_info_src(inet_ntoa(ppkt->ip->ip_src),
269                                         ntohl(stcp->th_seq),
270                                         ntohl(stcp->th_ack),
271                                         res, stcp->th_flags,
272                                         spkt->size);
273 
274         trace_colo_compare_pkt_info_dst(inet_ntoa(ppkt->ip->ip_dst),
275                                         ntohl(ptcp->th_seq),
276                                         ntohl(ptcp->th_ack),
277                                         res, ptcp->th_flags,
278                                         ppkt->size);
279 
280         qemu_hexdump((char *)ppkt->data, stderr,
281                      "colo-compare ppkt", ppkt->size);
282         qemu_hexdump((char *)spkt->data, stderr,
283                      "colo-compare spkt", spkt->size);
284     }
285 
286     return res;
287 }
288 
289 /*
290  * Called from the compare thread on the primary
291  * for compare udp packet
292  */
293 static int colo_packet_compare_udp(Packet *spkt, Packet *ppkt)
294 {
295     int ret;
296     int network_header_length = ppkt->ip->ip_hl * 4;
297 
298     trace_colo_compare_main("compare udp");
299 
300     /*
301      * Because of ppkt and spkt are both in the same connection,
302      * The ppkt's src ip, dst ip, src port, dst port, ip_proto all are
303      * same with spkt. In addition, IP header's Identification is a random
304      * field, we can handle it in IP fragmentation function later.
305      * COLO just concern the response net packet payload from primary guest
306      * and secondary guest are same or not, So we ignored all IP header include
307      * other field like TOS,TTL,IP Checksum. we only need to compare
308      * the ip payload here.
309      */
310     ret = colo_packet_compare_common(ppkt, spkt,
311                                      network_header_length + ETH_HLEN);
312 
313     if (ret) {
314         trace_colo_compare_udp_miscompare("primary pkt size", ppkt->size);
315         trace_colo_compare_udp_miscompare("Secondary pkt size", spkt->size);
316         if (trace_event_get_state(TRACE_COLO_COMPARE_MISCOMPARE)) {
317             qemu_hexdump((char *)ppkt->data, stderr, "colo-compare pri pkt",
318                          ppkt->size);
319             qemu_hexdump((char *)spkt->data, stderr, "colo-compare sec pkt",
320                          spkt->size);
321         }
322     }
323 
324     return ret;
325 }
326 
327 /*
328  * Called from the compare thread on the primary
329  * for compare icmp packet
330  */
331 static int colo_packet_compare_icmp(Packet *spkt, Packet *ppkt)
332 {
333     int network_header_length = ppkt->ip->ip_hl * 4;
334 
335     trace_colo_compare_main("compare icmp");
336 
337     /*
338      * Because of ppkt and spkt are both in the same connection,
339      * The ppkt's src ip, dst ip, src port, dst port, ip_proto all are
340      * same with spkt. In addition, IP header's Identification is a random
341      * field, we can handle it in IP fragmentation function later.
342      * COLO just concern the response net packet payload from primary guest
343      * and secondary guest are same or not, So we ignored all IP header include
344      * other field like TOS,TTL,IP Checksum. we only need to compare
345      * the ip payload here.
346      */
347     if (colo_packet_compare_common(ppkt, spkt,
348                                    network_header_length + ETH_HLEN)) {
349         trace_colo_compare_icmp_miscompare("primary pkt size",
350                                            ppkt->size);
351         trace_colo_compare_icmp_miscompare("Secondary pkt size",
352                                            spkt->size);
353         if (trace_event_get_state(TRACE_COLO_COMPARE_MISCOMPARE)) {
354             qemu_hexdump((char *)ppkt->data, stderr, "colo-compare pri pkt",
355                          ppkt->size);
356             qemu_hexdump((char *)spkt->data, stderr, "colo-compare sec pkt",
357                          spkt->size);
358         }
359         return -1;
360     } else {
361         return 0;
362     }
363 }
364 
365 /*
366  * Called from the compare thread on the primary
367  * for compare other packet
368  */
369 static int colo_packet_compare_other(Packet *spkt, Packet *ppkt)
370 {
371     trace_colo_compare_main("compare other");
372     if (trace_event_get_state(TRACE_COLO_COMPARE_MISCOMPARE)) {
373         char pri_ip_src[20], pri_ip_dst[20], sec_ip_src[20], sec_ip_dst[20];
374 
375         strcpy(pri_ip_src, inet_ntoa(ppkt->ip->ip_src));
376         strcpy(pri_ip_dst, inet_ntoa(ppkt->ip->ip_dst));
377         strcpy(sec_ip_src, inet_ntoa(spkt->ip->ip_src));
378         strcpy(sec_ip_dst, inet_ntoa(spkt->ip->ip_dst));
379 
380         trace_colo_compare_ip_info(ppkt->size, pri_ip_src,
381                                    pri_ip_dst, spkt->size,
382                                    sec_ip_src, sec_ip_dst);
383     }
384 
385     return colo_packet_compare_common(ppkt, spkt, 0);
386 }
387 
388 static int colo_old_packet_check_one(Packet *pkt, int64_t *check_time)
389 {
390     int64_t now = qemu_clock_get_ms(QEMU_CLOCK_HOST);
391 
392     if ((now - pkt->creation_ms) > (*check_time)) {
393         trace_colo_old_packet_check_found(pkt->creation_ms);
394         return 0;
395     } else {
396         return 1;
397     }
398 }
399 
400 static int colo_old_packet_check_one_conn(Connection *conn,
401                                           void *user_data)
402 {
403     GList *result = NULL;
404     int64_t check_time = REGULAR_PACKET_CHECK_MS;
405 
406     result = g_queue_find_custom(&conn->primary_list,
407                                  &check_time,
408                                  (GCompareFunc)colo_old_packet_check_one);
409 
410     if (result) {
411         /* do checkpoint will flush old packet */
412         /* TODO: colo_notify_checkpoint();*/
413         return 0;
414     }
415 
416     return 1;
417 }
418 
419 /*
420  * Look for old packets that the secondary hasn't matched,
421  * if we have some then we have to checkpoint to wake
422  * the secondary up.
423  */
424 static void colo_old_packet_check(void *opaque)
425 {
426     CompareState *s = opaque;
427 
428     /*
429      * If we find one old packet, stop finding job and notify
430      * COLO frame do checkpoint.
431      */
432     g_queue_find_custom(&s->conn_list, NULL,
433                         (GCompareFunc)colo_old_packet_check_one_conn);
434 }
435 
436 /*
437  * Called from the compare thread on the primary
438  * for compare connection
439  */
440 static void colo_compare_connection(void *opaque, void *user_data)
441 {
442     CompareState *s = user_data;
443     Connection *conn = opaque;
444     Packet *pkt = NULL;
445     GList *result = NULL;
446     int ret;
447 
448     while (!g_queue_is_empty(&conn->primary_list) &&
449            !g_queue_is_empty(&conn->secondary_list)) {
450         pkt = g_queue_pop_tail(&conn->primary_list);
451         switch (conn->ip_proto) {
452         case IPPROTO_TCP:
453             result = g_queue_find_custom(&conn->secondary_list,
454                      pkt, (GCompareFunc)colo_packet_compare_tcp);
455             break;
456         case IPPROTO_UDP:
457             result = g_queue_find_custom(&conn->secondary_list,
458                      pkt, (GCompareFunc)colo_packet_compare_udp);
459             break;
460         case IPPROTO_ICMP:
461             result = g_queue_find_custom(&conn->secondary_list,
462                      pkt, (GCompareFunc)colo_packet_compare_icmp);
463             break;
464         default:
465             result = g_queue_find_custom(&conn->secondary_list,
466                      pkt, (GCompareFunc)colo_packet_compare_other);
467             break;
468         }
469 
470         if (result) {
471             ret = compare_chr_send(&s->chr_out, pkt->data, pkt->size);
472             if (ret < 0) {
473                 error_report("colo_send_primary_packet failed");
474             }
475             trace_colo_compare_main("packet same and release packet");
476             g_queue_remove(&conn->secondary_list, result->data);
477             packet_destroy(pkt, NULL);
478         } else {
479             /*
480              * If one packet arrive late, the secondary_list or
481              * primary_list will be empty, so we can't compare it
482              * until next comparison.
483              */
484             trace_colo_compare_main("packet different");
485             g_queue_push_tail(&conn->primary_list, pkt);
486             /* TODO: colo_notify_checkpoint();*/
487             break;
488         }
489     }
490 }
491 
492 static int compare_chr_send(CharBackend *out,
493                             const uint8_t *buf,
494                             uint32_t size)
495 {
496     int ret = 0;
497     uint32_t len = htonl(size);
498 
499     if (!size) {
500         return 0;
501     }
502 
503     ret = qemu_chr_fe_write_all(out, (uint8_t *)&len, sizeof(len));
504     if (ret != sizeof(len)) {
505         goto err;
506     }
507 
508     ret = qemu_chr_fe_write_all(out, (uint8_t *)buf, size);
509     if (ret != size) {
510         goto err;
511     }
512 
513     return 0;
514 
515 err:
516     return ret < 0 ? ret : -EIO;
517 }
518 
519 static int compare_chr_can_read(void *opaque)
520 {
521     return COMPARE_READ_LEN_MAX;
522 }
523 
524 /*
525  * Called from the main thread on the primary for packets
526  * arriving over the socket from the primary.
527  */
528 static void compare_pri_chr_in(void *opaque, const uint8_t *buf, int size)
529 {
530     CompareState *s = COLO_COMPARE(opaque);
531     int ret;
532 
533     ret = net_fill_rstate(&s->pri_rs, buf, size);
534     if (ret == -1) {
535         qemu_chr_fe_set_handlers(&s->chr_pri_in, NULL, NULL, NULL,
536                                  NULL, NULL, true);
537         error_report("colo-compare primary_in error");
538     }
539 }
540 
541 /*
542  * Called from the main thread on the primary for packets
543  * arriving over the socket from the secondary.
544  */
545 static void compare_sec_chr_in(void *opaque, const uint8_t *buf, int size)
546 {
547     CompareState *s = COLO_COMPARE(opaque);
548     int ret;
549 
550     ret = net_fill_rstate(&s->sec_rs, buf, size);
551     if (ret == -1) {
552         qemu_chr_fe_set_handlers(&s->chr_sec_in, NULL, NULL, NULL,
553                                  NULL, NULL, true);
554         error_report("colo-compare secondary_in error");
555     }
556 }
557 
558 /*
559  * Check old packet regularly so it can watch for any packets
560  * that the secondary hasn't produced equivalents of.
561  */
562 static gboolean check_old_packet_regular(void *opaque)
563 {
564     CompareState *s = opaque;
565 
566     /* if have old packet we will notify checkpoint */
567     colo_old_packet_check(s);
568 
569     return TRUE;
570 }
571 
572 static void *colo_compare_thread(void *opaque)
573 {
574     CompareState *s = opaque;
575     GSource *timeout_source;
576 
577     s->worker_context = g_main_context_new();
578 
579     qemu_chr_fe_set_handlers(&s->chr_pri_in, compare_chr_can_read,
580                           compare_pri_chr_in, NULL, s, s->worker_context, true);
581     qemu_chr_fe_set_handlers(&s->chr_sec_in, compare_chr_can_read,
582                           compare_sec_chr_in, NULL, s, s->worker_context, true);
583 
584     s->compare_loop = g_main_loop_new(s->worker_context, FALSE);
585 
586     /* To kick any packets that the secondary doesn't match */
587     timeout_source = g_timeout_source_new(REGULAR_PACKET_CHECK_MS);
588     g_source_set_callback(timeout_source,
589                           (GSourceFunc)check_old_packet_regular, s, NULL);
590     g_source_attach(timeout_source, s->worker_context);
591 
592     g_main_loop_run(s->compare_loop);
593 
594     g_source_unref(timeout_source);
595     g_main_loop_unref(s->compare_loop);
596     g_main_context_unref(s->worker_context);
597     return NULL;
598 }
599 
600 static char *compare_get_pri_indev(Object *obj, Error **errp)
601 {
602     CompareState *s = COLO_COMPARE(obj);
603 
604     return g_strdup(s->pri_indev);
605 }
606 
607 static void compare_set_pri_indev(Object *obj, const char *value, Error **errp)
608 {
609     CompareState *s = COLO_COMPARE(obj);
610 
611     g_free(s->pri_indev);
612     s->pri_indev = g_strdup(value);
613 }
614 
615 static char *compare_get_sec_indev(Object *obj, Error **errp)
616 {
617     CompareState *s = COLO_COMPARE(obj);
618 
619     return g_strdup(s->sec_indev);
620 }
621 
622 static void compare_set_sec_indev(Object *obj, const char *value, Error **errp)
623 {
624     CompareState *s = COLO_COMPARE(obj);
625 
626     g_free(s->sec_indev);
627     s->sec_indev = g_strdup(value);
628 }
629 
630 static char *compare_get_outdev(Object *obj, Error **errp)
631 {
632     CompareState *s = COLO_COMPARE(obj);
633 
634     return g_strdup(s->outdev);
635 }
636 
637 static void compare_set_outdev(Object *obj, const char *value, Error **errp)
638 {
639     CompareState *s = COLO_COMPARE(obj);
640 
641     g_free(s->outdev);
642     s->outdev = g_strdup(value);
643 }
644 
645 static void compare_pri_rs_finalize(SocketReadState *pri_rs)
646 {
647     CompareState *s = container_of(pri_rs, CompareState, pri_rs);
648 
649     if (packet_enqueue(s, PRIMARY_IN)) {
650         trace_colo_compare_main("primary: unsupported packet in");
651         compare_chr_send(&s->chr_out, pri_rs->buf, pri_rs->packet_len);
652     } else {
653         /* compare connection */
654         g_queue_foreach(&s->conn_list, colo_compare_connection, s);
655     }
656 }
657 
658 static void compare_sec_rs_finalize(SocketReadState *sec_rs)
659 {
660     CompareState *s = container_of(sec_rs, CompareState, sec_rs);
661 
662     if (packet_enqueue(s, SECONDARY_IN)) {
663         trace_colo_compare_main("secondary: unsupported packet in");
664     } else {
665         /* compare connection */
666         g_queue_foreach(&s->conn_list, colo_compare_connection, s);
667     }
668 }
669 
670 
671 /*
672  * Return 0 is success.
673  * Return 1 is failed.
674  */
675 static int find_and_check_chardev(Chardev **chr,
676                                   char *chr_name,
677                                   Error **errp)
678 {
679     *chr = qemu_chr_find(chr_name);
680     if (*chr == NULL) {
681         error_setg(errp, "Device '%s' not found",
682                    chr_name);
683         return 1;
684     }
685 
686     if (!qemu_chr_has_feature(*chr, QEMU_CHAR_FEATURE_RECONNECTABLE)) {
687         error_setg(errp, "chardev \"%s\" is not reconnectable",
688                    chr_name);
689         return 1;
690     }
691 
692     return 0;
693 }
694 
695 /*
696  * Called from the main thread on the primary
697  * to setup colo-compare.
698  */
699 static void colo_compare_complete(UserCreatable *uc, Error **errp)
700 {
701     CompareState *s = COLO_COMPARE(uc);
702     Chardev *chr;
703     char thread_name[64];
704     static int compare_id;
705 
706     if (!s->pri_indev || !s->sec_indev || !s->outdev) {
707         error_setg(errp, "colo compare needs 'primary_in' ,"
708                    "'secondary_in','outdev' property set");
709         return;
710     } else if (!strcmp(s->pri_indev, s->outdev) ||
711                !strcmp(s->sec_indev, s->outdev) ||
712                !strcmp(s->pri_indev, s->sec_indev)) {
713         error_setg(errp, "'indev' and 'outdev' could not be same "
714                    "for compare module");
715         return;
716     }
717 
718     if (find_and_check_chardev(&chr, s->pri_indev, errp) ||
719         !qemu_chr_fe_init(&s->chr_pri_in, chr, errp)) {
720         return;
721     }
722 
723     if (find_and_check_chardev(&chr, s->sec_indev, errp) ||
724         !qemu_chr_fe_init(&s->chr_sec_in, chr, errp)) {
725         return;
726     }
727 
728     if (find_and_check_chardev(&chr, s->outdev, errp) ||
729         !qemu_chr_fe_init(&s->chr_out, chr, errp)) {
730         return;
731     }
732 
733     net_socket_rs_init(&s->pri_rs, compare_pri_rs_finalize);
734     net_socket_rs_init(&s->sec_rs, compare_sec_rs_finalize);
735 
736     g_queue_init(&s->conn_list);
737 
738     s->connection_track_table = g_hash_table_new_full(connection_key_hash,
739                                                       connection_key_equal,
740                                                       g_free,
741                                                       connection_destroy);
742 
743     sprintf(thread_name, "colo-compare %d", compare_id);
744     qemu_thread_create(&s->thread, thread_name,
745                        colo_compare_thread, s,
746                        QEMU_THREAD_JOINABLE);
747     compare_id++;
748 
749     return;
750 }
751 
752 static void colo_flush_packets(void *opaque, void *user_data)
753 {
754     CompareState *s = user_data;
755     Connection *conn = opaque;
756     Packet *pkt = NULL;
757 
758     while (!g_queue_is_empty(&conn->primary_list)) {
759         pkt = g_queue_pop_head(&conn->primary_list);
760         compare_chr_send(&s->chr_out, pkt->data, pkt->size);
761         packet_destroy(pkt, NULL);
762     }
763     while (!g_queue_is_empty(&conn->secondary_list)) {
764         pkt = g_queue_pop_head(&conn->secondary_list);
765         packet_destroy(pkt, NULL);
766     }
767 }
768 
769 static void colo_compare_class_init(ObjectClass *oc, void *data)
770 {
771     UserCreatableClass *ucc = USER_CREATABLE_CLASS(oc);
772 
773     ucc->complete = colo_compare_complete;
774 }
775 
776 static void colo_compare_init(Object *obj)
777 {
778     object_property_add_str(obj, "primary_in",
779                             compare_get_pri_indev, compare_set_pri_indev,
780                             NULL);
781     object_property_add_str(obj, "secondary_in",
782                             compare_get_sec_indev, compare_set_sec_indev,
783                             NULL);
784     object_property_add_str(obj, "outdev",
785                             compare_get_outdev, compare_set_outdev,
786                             NULL);
787 }
788 
789 static void colo_compare_finalize(Object *obj)
790 {
791     CompareState *s = COLO_COMPARE(obj);
792 
793     qemu_chr_fe_set_handlers(&s->chr_pri_in, NULL, NULL, NULL, NULL,
794                              s->worker_context, true);
795     qemu_chr_fe_set_handlers(&s->chr_sec_in, NULL, NULL, NULL, NULL,
796                              s->worker_context, true);
797     qemu_chr_fe_deinit(&s->chr_out);
798 
799     g_main_loop_quit(s->compare_loop);
800     qemu_thread_join(&s->thread);
801 
802     /* Release all unhandled packets after compare thead exited */
803     g_queue_foreach(&s->conn_list, colo_flush_packets, s);
804 
805     g_queue_clear(&s->conn_list);
806 
807     g_hash_table_destroy(s->connection_track_table);
808     g_free(s->pri_indev);
809     g_free(s->sec_indev);
810     g_free(s->outdev);
811 }
812 
813 static const TypeInfo colo_compare_info = {
814     .name = TYPE_COLO_COMPARE,
815     .parent = TYPE_OBJECT,
816     .instance_size = sizeof(CompareState),
817     .instance_init = colo_compare_init,
818     .instance_finalize = colo_compare_finalize,
819     .class_size = sizeof(CompareClass),
820     .class_init = colo_compare_class_init,
821     .interfaces = (InterfaceInfo[]) {
822         { TYPE_USER_CREATABLE },
823         { }
824     }
825 };
826 
827 static void register_types(void)
828 {
829     type_register_static(&colo_compare_info);
830 }
831 
832 type_init(register_types);
833