xref: /openbmc/qemu/net/colo-compare.c (revision 8908eb1a)
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 "chardev/char-fe.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     bool vnet_hdr;
77 
78     /* connection list: the connections belonged to this NIC could be found
79      * in this list.
80      * element type: Connection
81      */
82     GQueue conn_list;
83     /* hashtable to save connection */
84     GHashTable *connection_track_table;
85     /* compare thread, a thread for each NIC */
86     QemuThread thread;
87 
88     GMainContext *worker_context;
89     GMainLoop *compare_loop;
90 } CompareState;
91 
92 typedef struct CompareClass {
93     ObjectClass parent_class;
94 } CompareClass;
95 
96 enum {
97     PRIMARY_IN = 0,
98     SECONDARY_IN,
99 };
100 
101 static int compare_chr_send(CompareState *s,
102                             const uint8_t *buf,
103                             uint32_t size,
104                             uint32_t vnet_hdr_len);
105 
106 static gint seq_sorter(Packet *a, Packet *b, gpointer data)
107 {
108     struct tcphdr *atcp, *btcp;
109 
110     atcp = (struct tcphdr *)(a->transport_header);
111     btcp = (struct tcphdr *)(b->transport_header);
112     return ntohl(atcp->th_seq) - ntohl(btcp->th_seq);
113 }
114 
115 /*
116  * Return 0 on success, if return -1 means the pkt
117  * is unsupported(arp and ipv6) and will be sent later
118  */
119 static int packet_enqueue(CompareState *s, int mode)
120 {
121     ConnectionKey key;
122     Packet *pkt = NULL;
123     Connection *conn;
124 
125     if (mode == PRIMARY_IN) {
126         pkt = packet_new(s->pri_rs.buf,
127                          s->pri_rs.packet_len,
128                          s->pri_rs.vnet_hdr_len);
129     } else {
130         pkt = packet_new(s->sec_rs.buf,
131                          s->sec_rs.packet_len,
132                          s->sec_rs.vnet_hdr_len);
133     }
134 
135     if (parse_packet_early(pkt)) {
136         packet_destroy(pkt, NULL);
137         pkt = NULL;
138         return -1;
139     }
140     fill_connection_key(pkt, &key);
141 
142     conn = connection_get(s->connection_track_table,
143                           &key,
144                           &s->conn_list);
145 
146     if (!conn->processing) {
147         g_queue_push_tail(&s->conn_list, conn);
148         conn->processing = true;
149     }
150 
151     if (mode == PRIMARY_IN) {
152         if (g_queue_get_length(&conn->primary_list) <=
153                                MAX_QUEUE_SIZE) {
154             g_queue_push_tail(&conn->primary_list, pkt);
155             if (conn->ip_proto == IPPROTO_TCP) {
156                 g_queue_sort(&conn->primary_list,
157                              (GCompareDataFunc)seq_sorter,
158                              NULL);
159             }
160         } else {
161             error_report("colo compare primary queue size too big,"
162                          "drop packet");
163         }
164     } else {
165         if (g_queue_get_length(&conn->secondary_list) <=
166                                MAX_QUEUE_SIZE) {
167             g_queue_push_tail(&conn->secondary_list, pkt);
168             if (conn->ip_proto == IPPROTO_TCP) {
169                 g_queue_sort(&conn->secondary_list,
170                              (GCompareDataFunc)seq_sorter,
171                              NULL);
172             }
173         } else {
174             error_report("colo compare secondary queue size too big,"
175                          "drop packet");
176         }
177     }
178 
179     return 0;
180 }
181 
182 /*
183  * The IP packets sent by primary and secondary
184  * will be compared in here
185  * TODO support ip fragment, Out-Of-Order
186  * return:    0  means packet same
187  *            > 0 || < 0 means packet different
188  */
189 static int colo_packet_compare_common(Packet *ppkt, Packet *spkt, int offset)
190 {
191     if (trace_event_get_state_backends(TRACE_COLO_COMPARE_MISCOMPARE)) {
192         char pri_ip_src[20], pri_ip_dst[20], sec_ip_src[20], sec_ip_dst[20];
193 
194         strcpy(pri_ip_src, inet_ntoa(ppkt->ip->ip_src));
195         strcpy(pri_ip_dst, inet_ntoa(ppkt->ip->ip_dst));
196         strcpy(sec_ip_src, inet_ntoa(spkt->ip->ip_src));
197         strcpy(sec_ip_dst, inet_ntoa(spkt->ip->ip_dst));
198 
199         trace_colo_compare_ip_info(ppkt->size, pri_ip_src,
200                                    pri_ip_dst, spkt->size,
201                                    sec_ip_src, sec_ip_dst);
202     }
203 
204     offset = ppkt->vnet_hdr_len + offset;
205 
206     if (ppkt->size == spkt->size) {
207         return memcmp(ppkt->data + offset,
208                       spkt->data + offset,
209                       spkt->size - offset);
210     } else {
211         trace_colo_compare_main("Net packet size are not the same");
212         return -1;
213     }
214 }
215 
216 /*
217  * Called from the compare thread on the primary
218  * for compare tcp packet
219  * compare_tcp copied from Dr. David Alan Gilbert's branch
220  */
221 static int colo_packet_compare_tcp(Packet *spkt, Packet *ppkt)
222 {
223     struct tcphdr *ptcp, *stcp;
224     int res;
225 
226     trace_colo_compare_main("compare tcp");
227 
228     ptcp = (struct tcphdr *)ppkt->transport_header;
229     stcp = (struct tcphdr *)spkt->transport_header;
230 
231     /*
232      * The 'identification' field in the IP header is *very* random
233      * it almost never matches.  Fudge this by ignoring differences in
234      * unfragmented packets; they'll normally sort themselves out if different
235      * anyway, and it should recover at the TCP level.
236      * An alternative would be to get both the primary and secondary to rewrite
237      * somehow; but that would need some sync traffic to sync the state
238      */
239     if (ntohs(ppkt->ip->ip_off) & IP_DF) {
240         spkt->ip->ip_id = ppkt->ip->ip_id;
241         /* and the sum will be different if the IDs were different */
242         spkt->ip->ip_sum = ppkt->ip->ip_sum;
243     }
244 
245     /*
246      * Check tcp header length for tcp option field.
247      * th_off > 5 means this tcp packet have options field.
248      * The tcp options maybe always different.
249      * for example:
250      * From RFC 7323.
251      * TCP Timestamps option (TSopt):
252      * Kind: 8
253      *
254      * Length: 10 bytes
255      *
256      *    +-------+-------+---------------------+---------------------+
257      *    |Kind=8 |  10   |   TS Value (TSval)  |TS Echo Reply (TSecr)|
258      *    +-------+-------+---------------------+---------------------+
259      *       1       1              4                     4
260      *
261      * In this case the primary guest's timestamp always different with
262      * the secondary guest's timestamp. COLO just focus on payload,
263      * so we just need skip this field.
264      */
265     if (ptcp->th_off > 5) {
266         ptrdiff_t tcp_offset;
267 
268         tcp_offset = ppkt->transport_header - (uint8_t *)ppkt->data
269                      + (ptcp->th_off * 4) - ppkt->vnet_hdr_len;
270         res = colo_packet_compare_common(ppkt, spkt, tcp_offset);
271     } else if (ptcp->th_sum == stcp->th_sum) {
272         res = colo_packet_compare_common(ppkt, spkt, ETH_HLEN);
273     } else {
274         res = -1;
275     }
276 
277     if (res != 0 &&
278         trace_event_get_state_backends(TRACE_COLO_COMPARE_MISCOMPARE)) {
279         char pri_ip_src[20], pri_ip_dst[20], sec_ip_src[20], sec_ip_dst[20];
280 
281         strcpy(pri_ip_src, inet_ntoa(ppkt->ip->ip_src));
282         strcpy(pri_ip_dst, inet_ntoa(ppkt->ip->ip_dst));
283         strcpy(sec_ip_src, inet_ntoa(spkt->ip->ip_src));
284         strcpy(sec_ip_dst, inet_ntoa(spkt->ip->ip_dst));
285 
286         trace_colo_compare_ip_info(ppkt->size, pri_ip_src,
287                                    pri_ip_dst, spkt->size,
288                                    sec_ip_src, sec_ip_dst);
289 
290         trace_colo_compare_tcp_info("pri tcp packet",
291                                     ntohl(ptcp->th_seq),
292                                     ntohl(ptcp->th_ack),
293                                     res, ptcp->th_flags,
294                                     ppkt->size);
295 
296         trace_colo_compare_tcp_info("sec tcp packet",
297                                     ntohl(stcp->th_seq),
298                                     ntohl(stcp->th_ack),
299                                     res, stcp->th_flags,
300                                     spkt->size);
301 
302         qemu_hexdump((char *)ppkt->data, stderr,
303                      "colo-compare ppkt", ppkt->size);
304         qemu_hexdump((char *)spkt->data, stderr,
305                      "colo-compare spkt", spkt->size);
306     }
307 
308     return res;
309 }
310 
311 /*
312  * Called from the compare thread on the primary
313  * for compare udp packet
314  */
315 static int colo_packet_compare_udp(Packet *spkt, Packet *ppkt)
316 {
317     int ret;
318     int network_header_length = ppkt->ip->ip_hl * 4;
319 
320     trace_colo_compare_main("compare udp");
321 
322     /*
323      * Because of ppkt and spkt are both in the same connection,
324      * The ppkt's src ip, dst ip, src port, dst port, ip_proto all are
325      * same with spkt. In addition, IP header's Identification is a random
326      * field, we can handle it in IP fragmentation function later.
327      * COLO just concern the response net packet payload from primary guest
328      * and secondary guest are same or not, So we ignored all IP header include
329      * other field like TOS,TTL,IP Checksum. we only need to compare
330      * the ip payload here.
331      */
332     ret = colo_packet_compare_common(ppkt, spkt,
333                                      network_header_length + ETH_HLEN);
334 
335     if (ret) {
336         trace_colo_compare_udp_miscompare("primary pkt size", ppkt->size);
337         trace_colo_compare_udp_miscompare("Secondary pkt size", spkt->size);
338         if (trace_event_get_state_backends(TRACE_COLO_COMPARE_MISCOMPARE)) {
339             qemu_hexdump((char *)ppkt->data, stderr, "colo-compare pri pkt",
340                          ppkt->size);
341             qemu_hexdump((char *)spkt->data, stderr, "colo-compare sec pkt",
342                          spkt->size);
343         }
344     }
345 
346     return ret;
347 }
348 
349 /*
350  * Called from the compare thread on the primary
351  * for compare icmp packet
352  */
353 static int colo_packet_compare_icmp(Packet *spkt, Packet *ppkt)
354 {
355     int network_header_length = ppkt->ip->ip_hl * 4;
356 
357     trace_colo_compare_main("compare icmp");
358 
359     /*
360      * Because of ppkt and spkt are both in the same connection,
361      * The ppkt's src ip, dst ip, src port, dst port, ip_proto all are
362      * same with spkt. In addition, IP header's Identification is a random
363      * field, we can handle it in IP fragmentation function later.
364      * COLO just concern the response net packet payload from primary guest
365      * and secondary guest are same or not, So we ignored all IP header include
366      * other field like TOS,TTL,IP Checksum. we only need to compare
367      * the ip payload here.
368      */
369     if (colo_packet_compare_common(ppkt, spkt,
370                                    network_header_length + ETH_HLEN)) {
371         trace_colo_compare_icmp_miscompare("primary pkt size",
372                                            ppkt->size);
373         trace_colo_compare_icmp_miscompare("Secondary pkt size",
374                                            spkt->size);
375         if (trace_event_get_state_backends(TRACE_COLO_COMPARE_MISCOMPARE)) {
376             qemu_hexdump((char *)ppkt->data, stderr, "colo-compare pri pkt",
377                          ppkt->size);
378             qemu_hexdump((char *)spkt->data, stderr, "colo-compare sec pkt",
379                          spkt->size);
380         }
381         return -1;
382     } else {
383         return 0;
384     }
385 }
386 
387 /*
388  * Called from the compare thread on the primary
389  * for compare other packet
390  */
391 static int colo_packet_compare_other(Packet *spkt, Packet *ppkt)
392 {
393     trace_colo_compare_main("compare other");
394     if (trace_event_get_state_backends(TRACE_COLO_COMPARE_MISCOMPARE)) {
395         char pri_ip_src[20], pri_ip_dst[20], sec_ip_src[20], sec_ip_dst[20];
396 
397         strcpy(pri_ip_src, inet_ntoa(ppkt->ip->ip_src));
398         strcpy(pri_ip_dst, inet_ntoa(ppkt->ip->ip_dst));
399         strcpy(sec_ip_src, inet_ntoa(spkt->ip->ip_src));
400         strcpy(sec_ip_dst, inet_ntoa(spkt->ip->ip_dst));
401 
402         trace_colo_compare_ip_info(ppkt->size, pri_ip_src,
403                                    pri_ip_dst, spkt->size,
404                                    sec_ip_src, sec_ip_dst);
405     }
406 
407     return colo_packet_compare_common(ppkt, spkt, 0);
408 }
409 
410 static int colo_old_packet_check_one(Packet *pkt, int64_t *check_time)
411 {
412     int64_t now = qemu_clock_get_ms(QEMU_CLOCK_HOST);
413 
414     if ((now - pkt->creation_ms) > (*check_time)) {
415         trace_colo_old_packet_check_found(pkt->creation_ms);
416         return 0;
417     } else {
418         return 1;
419     }
420 }
421 
422 static int colo_old_packet_check_one_conn(Connection *conn,
423                                           void *user_data)
424 {
425     GList *result = NULL;
426     int64_t check_time = REGULAR_PACKET_CHECK_MS;
427 
428     result = g_queue_find_custom(&conn->primary_list,
429                                  &check_time,
430                                  (GCompareFunc)colo_old_packet_check_one);
431 
432     if (result) {
433         /* do checkpoint will flush old packet */
434         /* TODO: colo_notify_checkpoint();*/
435         return 0;
436     }
437 
438     return 1;
439 }
440 
441 /*
442  * Look for old packets that the secondary hasn't matched,
443  * if we have some then we have to checkpoint to wake
444  * the secondary up.
445  */
446 static void colo_old_packet_check(void *opaque)
447 {
448     CompareState *s = opaque;
449 
450     /*
451      * If we find one old packet, stop finding job and notify
452      * COLO frame do checkpoint.
453      */
454     g_queue_find_custom(&s->conn_list, NULL,
455                         (GCompareFunc)colo_old_packet_check_one_conn);
456 }
457 
458 /*
459  * Called from the compare thread on the primary
460  * for compare connection
461  */
462 static void colo_compare_connection(void *opaque, void *user_data)
463 {
464     CompareState *s = user_data;
465     Connection *conn = opaque;
466     Packet *pkt = NULL;
467     GList *result = NULL;
468     int ret;
469 
470     while (!g_queue_is_empty(&conn->primary_list) &&
471            !g_queue_is_empty(&conn->secondary_list)) {
472         pkt = g_queue_pop_tail(&conn->primary_list);
473         switch (conn->ip_proto) {
474         case IPPROTO_TCP:
475             result = g_queue_find_custom(&conn->secondary_list,
476                      pkt, (GCompareFunc)colo_packet_compare_tcp);
477             break;
478         case IPPROTO_UDP:
479             result = g_queue_find_custom(&conn->secondary_list,
480                      pkt, (GCompareFunc)colo_packet_compare_udp);
481             break;
482         case IPPROTO_ICMP:
483             result = g_queue_find_custom(&conn->secondary_list,
484                      pkt, (GCompareFunc)colo_packet_compare_icmp);
485             break;
486         default:
487             result = g_queue_find_custom(&conn->secondary_list,
488                      pkt, (GCompareFunc)colo_packet_compare_other);
489             break;
490         }
491 
492         if (result) {
493             ret = compare_chr_send(s,
494                                    pkt->data,
495                                    pkt->size,
496                                    pkt->vnet_hdr_len);
497             if (ret < 0) {
498                 error_report("colo_send_primary_packet failed");
499             }
500             trace_colo_compare_main("packet same and release packet");
501             g_queue_remove(&conn->secondary_list, result->data);
502             packet_destroy(pkt, NULL);
503         } else {
504             /*
505              * If one packet arrive late, the secondary_list or
506              * primary_list will be empty, so we can't compare it
507              * until next comparison.
508              */
509             trace_colo_compare_main("packet different");
510             g_queue_push_tail(&conn->primary_list, pkt);
511             /* TODO: colo_notify_checkpoint();*/
512             break;
513         }
514     }
515 }
516 
517 static int compare_chr_send(CompareState *s,
518                             const uint8_t *buf,
519                             uint32_t size,
520                             uint32_t vnet_hdr_len)
521 {
522     int ret = 0;
523     uint32_t len = htonl(size);
524 
525     if (!size) {
526         return 0;
527     }
528 
529     ret = qemu_chr_fe_write_all(&s->chr_out, (uint8_t *)&len, sizeof(len));
530     if (ret != sizeof(len)) {
531         goto err;
532     }
533 
534     if (s->vnet_hdr) {
535         /*
536          * We send vnet header len make other module(like filter-redirector)
537          * know how to parse net packet correctly.
538          */
539         len = htonl(vnet_hdr_len);
540         ret = qemu_chr_fe_write_all(&s->chr_out, (uint8_t *)&len, sizeof(len));
541         if (ret != sizeof(len)) {
542             goto err;
543         }
544     }
545 
546     ret = qemu_chr_fe_write_all(&s->chr_out, (uint8_t *)buf, size);
547     if (ret != size) {
548         goto err;
549     }
550 
551     return 0;
552 
553 err:
554     return ret < 0 ? ret : -EIO;
555 }
556 
557 static int compare_chr_can_read(void *opaque)
558 {
559     return COMPARE_READ_LEN_MAX;
560 }
561 
562 /*
563  * Called from the main thread on the primary for packets
564  * arriving over the socket from the primary.
565  */
566 static void compare_pri_chr_in(void *opaque, const uint8_t *buf, int size)
567 {
568     CompareState *s = COLO_COMPARE(opaque);
569     int ret;
570 
571     ret = net_fill_rstate(&s->pri_rs, buf, size);
572     if (ret == -1) {
573         qemu_chr_fe_set_handlers(&s->chr_pri_in, NULL, NULL, NULL, NULL,
574                                  NULL, NULL, true);
575         error_report("colo-compare primary_in error");
576     }
577 }
578 
579 /*
580  * Called from the main thread on the primary for packets
581  * arriving over the socket from the secondary.
582  */
583 static void compare_sec_chr_in(void *opaque, const uint8_t *buf, int size)
584 {
585     CompareState *s = COLO_COMPARE(opaque);
586     int ret;
587 
588     ret = net_fill_rstate(&s->sec_rs, buf, size);
589     if (ret == -1) {
590         qemu_chr_fe_set_handlers(&s->chr_sec_in, NULL, NULL, NULL, NULL,
591                                  NULL, NULL, true);
592         error_report("colo-compare secondary_in error");
593     }
594 }
595 
596 /*
597  * Check old packet regularly so it can watch for any packets
598  * that the secondary hasn't produced equivalents of.
599  */
600 static gboolean check_old_packet_regular(void *opaque)
601 {
602     CompareState *s = opaque;
603 
604     /* if have old packet we will notify checkpoint */
605     colo_old_packet_check(s);
606 
607     return TRUE;
608 }
609 
610 static void *colo_compare_thread(void *opaque)
611 {
612     CompareState *s = opaque;
613     GSource *timeout_source;
614 
615     s->worker_context = g_main_context_new();
616 
617     qemu_chr_fe_set_handlers(&s->chr_pri_in, compare_chr_can_read,
618                              compare_pri_chr_in, NULL, NULL,
619                              s, s->worker_context, true);
620     qemu_chr_fe_set_handlers(&s->chr_sec_in, compare_chr_can_read,
621                              compare_sec_chr_in, NULL, NULL,
622                              s, s->worker_context, true);
623 
624     s->compare_loop = g_main_loop_new(s->worker_context, FALSE);
625 
626     /* To kick any packets that the secondary doesn't match */
627     timeout_source = g_timeout_source_new(REGULAR_PACKET_CHECK_MS);
628     g_source_set_callback(timeout_source,
629                           (GSourceFunc)check_old_packet_regular, s, NULL);
630     g_source_attach(timeout_source, s->worker_context);
631 
632     g_main_loop_run(s->compare_loop);
633 
634     g_source_unref(timeout_source);
635     g_main_loop_unref(s->compare_loop);
636     g_main_context_unref(s->worker_context);
637     return NULL;
638 }
639 
640 static char *compare_get_pri_indev(Object *obj, Error **errp)
641 {
642     CompareState *s = COLO_COMPARE(obj);
643 
644     return g_strdup(s->pri_indev);
645 }
646 
647 static void compare_set_pri_indev(Object *obj, const char *value, Error **errp)
648 {
649     CompareState *s = COLO_COMPARE(obj);
650 
651     g_free(s->pri_indev);
652     s->pri_indev = g_strdup(value);
653 }
654 
655 static char *compare_get_sec_indev(Object *obj, Error **errp)
656 {
657     CompareState *s = COLO_COMPARE(obj);
658 
659     return g_strdup(s->sec_indev);
660 }
661 
662 static void compare_set_sec_indev(Object *obj, const char *value, Error **errp)
663 {
664     CompareState *s = COLO_COMPARE(obj);
665 
666     g_free(s->sec_indev);
667     s->sec_indev = g_strdup(value);
668 }
669 
670 static char *compare_get_outdev(Object *obj, Error **errp)
671 {
672     CompareState *s = COLO_COMPARE(obj);
673 
674     return g_strdup(s->outdev);
675 }
676 
677 static void compare_set_outdev(Object *obj, const char *value, Error **errp)
678 {
679     CompareState *s = COLO_COMPARE(obj);
680 
681     g_free(s->outdev);
682     s->outdev = g_strdup(value);
683 }
684 
685 static bool compare_get_vnet_hdr(Object *obj, Error **errp)
686 {
687     CompareState *s = COLO_COMPARE(obj);
688 
689     return s->vnet_hdr;
690 }
691 
692 static void compare_set_vnet_hdr(Object *obj,
693                                  bool value,
694                                  Error **errp)
695 {
696     CompareState *s = COLO_COMPARE(obj);
697 
698     s->vnet_hdr = value;
699 }
700 
701 static void compare_pri_rs_finalize(SocketReadState *pri_rs)
702 {
703     CompareState *s = container_of(pri_rs, CompareState, pri_rs);
704 
705     if (packet_enqueue(s, PRIMARY_IN)) {
706         trace_colo_compare_main("primary: unsupported packet in");
707         compare_chr_send(s,
708                          pri_rs->buf,
709                          pri_rs->packet_len,
710                          pri_rs->vnet_hdr_len);
711     } else {
712         /* compare connection */
713         g_queue_foreach(&s->conn_list, colo_compare_connection, s);
714     }
715 }
716 
717 static void compare_sec_rs_finalize(SocketReadState *sec_rs)
718 {
719     CompareState *s = container_of(sec_rs, CompareState, sec_rs);
720 
721     if (packet_enqueue(s, SECONDARY_IN)) {
722         trace_colo_compare_main("secondary: unsupported packet in");
723     } else {
724         /* compare connection */
725         g_queue_foreach(&s->conn_list, colo_compare_connection, s);
726     }
727 }
728 
729 
730 /*
731  * Return 0 is success.
732  * Return 1 is failed.
733  */
734 static int find_and_check_chardev(Chardev **chr,
735                                   char *chr_name,
736                                   Error **errp)
737 {
738     *chr = qemu_chr_find(chr_name);
739     if (*chr == NULL) {
740         error_setg(errp, "Device '%s' not found",
741                    chr_name);
742         return 1;
743     }
744 
745     if (!qemu_chr_has_feature(*chr, QEMU_CHAR_FEATURE_RECONNECTABLE)) {
746         error_setg(errp, "chardev \"%s\" is not reconnectable",
747                    chr_name);
748         return 1;
749     }
750 
751     return 0;
752 }
753 
754 /*
755  * Called from the main thread on the primary
756  * to setup colo-compare.
757  */
758 static void colo_compare_complete(UserCreatable *uc, Error **errp)
759 {
760     CompareState *s = COLO_COMPARE(uc);
761     Chardev *chr;
762     char thread_name[64];
763     static int compare_id;
764 
765     if (!s->pri_indev || !s->sec_indev || !s->outdev) {
766         error_setg(errp, "colo compare needs 'primary_in' ,"
767                    "'secondary_in','outdev' property set");
768         return;
769     } else if (!strcmp(s->pri_indev, s->outdev) ||
770                !strcmp(s->sec_indev, s->outdev) ||
771                !strcmp(s->pri_indev, s->sec_indev)) {
772         error_setg(errp, "'indev' and 'outdev' could not be same "
773                    "for compare module");
774         return;
775     }
776 
777     if (find_and_check_chardev(&chr, s->pri_indev, errp) ||
778         !qemu_chr_fe_init(&s->chr_pri_in, chr, errp)) {
779         return;
780     }
781 
782     if (find_and_check_chardev(&chr, s->sec_indev, errp) ||
783         !qemu_chr_fe_init(&s->chr_sec_in, chr, errp)) {
784         return;
785     }
786 
787     if (find_and_check_chardev(&chr, s->outdev, errp) ||
788         !qemu_chr_fe_init(&s->chr_out, chr, errp)) {
789         return;
790     }
791 
792     net_socket_rs_init(&s->pri_rs, compare_pri_rs_finalize, s->vnet_hdr);
793     net_socket_rs_init(&s->sec_rs, compare_sec_rs_finalize, s->vnet_hdr);
794 
795     g_queue_init(&s->conn_list);
796 
797     s->connection_track_table = g_hash_table_new_full(connection_key_hash,
798                                                       connection_key_equal,
799                                                       g_free,
800                                                       connection_destroy);
801 
802     sprintf(thread_name, "colo-compare %d", compare_id);
803     qemu_thread_create(&s->thread, thread_name,
804                        colo_compare_thread, s,
805                        QEMU_THREAD_JOINABLE);
806     compare_id++;
807 
808     return;
809 }
810 
811 static void colo_flush_packets(void *opaque, void *user_data)
812 {
813     CompareState *s = user_data;
814     Connection *conn = opaque;
815     Packet *pkt = NULL;
816 
817     while (!g_queue_is_empty(&conn->primary_list)) {
818         pkt = g_queue_pop_head(&conn->primary_list);
819         compare_chr_send(s,
820                          pkt->data,
821                          pkt->size,
822                          pkt->vnet_hdr_len);
823         packet_destroy(pkt, NULL);
824     }
825     while (!g_queue_is_empty(&conn->secondary_list)) {
826         pkt = g_queue_pop_head(&conn->secondary_list);
827         packet_destroy(pkt, NULL);
828     }
829 }
830 
831 static void colo_compare_class_init(ObjectClass *oc, void *data)
832 {
833     UserCreatableClass *ucc = USER_CREATABLE_CLASS(oc);
834 
835     ucc->complete = colo_compare_complete;
836 }
837 
838 static void colo_compare_init(Object *obj)
839 {
840     CompareState *s = COLO_COMPARE(obj);
841 
842     object_property_add_str(obj, "primary_in",
843                             compare_get_pri_indev, compare_set_pri_indev,
844                             NULL);
845     object_property_add_str(obj, "secondary_in",
846                             compare_get_sec_indev, compare_set_sec_indev,
847                             NULL);
848     object_property_add_str(obj, "outdev",
849                             compare_get_outdev, compare_set_outdev,
850                             NULL);
851 
852     s->vnet_hdr = false;
853     object_property_add_bool(obj, "vnet_hdr_support", compare_get_vnet_hdr,
854                              compare_set_vnet_hdr, NULL);
855 }
856 
857 static void colo_compare_finalize(Object *obj)
858 {
859     CompareState *s = COLO_COMPARE(obj);
860 
861     qemu_chr_fe_deinit(&s->chr_pri_in, false);
862     qemu_chr_fe_deinit(&s->chr_sec_in, false);
863     qemu_chr_fe_deinit(&s->chr_out, false);
864 
865     g_main_loop_quit(s->compare_loop);
866     qemu_thread_join(&s->thread);
867 
868     /* Release all unhandled packets after compare thead exited */
869     g_queue_foreach(&s->conn_list, colo_flush_packets, s);
870 
871     g_queue_clear(&s->conn_list);
872 
873     g_hash_table_destroy(s->connection_track_table);
874     g_free(s->pri_indev);
875     g_free(s->sec_indev);
876     g_free(s->outdev);
877 }
878 
879 static const TypeInfo colo_compare_info = {
880     .name = TYPE_COLO_COMPARE,
881     .parent = TYPE_OBJECT,
882     .instance_size = sizeof(CompareState),
883     .instance_init = colo_compare_init,
884     .instance_finalize = colo_compare_finalize,
885     .class_size = sizeof(CompareClass),
886     .class_init = colo_compare_class_init,
887     .interfaces = (InterfaceInfo[]) {
888         { TYPE_USER_CREATABLE },
889         { }
890     }
891 };
892 
893 static void register_types(void)
894 {
895     type_register_static(&colo_compare_info);
896 }
897 
898 type_init(register_types);
899