migration/tcp.c

   1 /*
   2  * QEMU live migration
   3  *
   4  * Copyright IBM, Corp. 2008
   5  *
   6  * Authors:
   7  *  Anthony Liguori   <aliguori@us.ibm.com>
   8  *
   9  * This work is licensed under the terms of the GNU GPL, version 2.  See
  10  * the COPYING file in the top-level directory.
  11  *
  12  * Contributions after 2012-01-13 are licensed under the terms of the
  13  * GNU GPL, version 2 or (at your option) any later version.
  14  */
  15
  16 #include "qemu/osdep.h"
  17
  18 #include "qemu-common.h"
  19 #include "qemu/error-report.h"
  20 #include "qemu/sockets.h"
  21 #include "migration/migration.h"
  22 #include "migration/qemu-file.h"
  23 #include "block/block.h"
  24 #include "qemu/main-loop.h"
  25
  26 //#define DEBUG_MIGRATION_TCP
  27
  28 #ifdef DEBUG_MIGRATION_TCP
  29 #define DPRINTF(fmt, ...) \
  30     do { printf("migration-tcp: " fmt, ## __VA_ARGS__); } while (0)
  31 #else
  32 #define DPRINTF(fmt, ...) \
  33     do { } while (0)
  34 #endif
  35
  36 static void tcp_wait_for_connect(int fd, Error *err, void *opaque)
  37 {
  38     MigrationState *s = opaque;
  39
  40     if (fd < 0) {
  41         DPRINTF("migrate connect error: %s\n", error_get_pretty(err));
  42         s->to_dst_file = NULL;
  43         migrate_fd_error(s);
  44     } else {
  45         DPRINTF("migrate connect success\n");
  46         s->to_dst_file = qemu_fopen_socket(fd, "wb");
  47         migrate_fd_connect(s);
  48     }
  49 }
  50
  51 void tcp_start_outgoing_migration(MigrationState *s, const char *host_port, Error **errp)
  52 {
  53     inet_nonblocking_connect(host_port, tcp_wait_for_connect, s, errp);
  54 }
  55
  56 static void tcp_accept_incoming_migration(void *opaque)
  57 {
  58     struct sockaddr_in addr;
  59     socklen_t addrlen = sizeof(addr);
  60     int s = (intptr_t)opaque;
  61     QEMUFile *f;
  62     int c;
  63
  64     do {
  65         c = qemu_accept(s, (struct sockaddr *)&addr, &addrlen);
  66     } while (c < 0 && errno == EINTR);
  67     qemu_set_fd_handler(s, NULL, NULL, NULL);
  68     closesocket(s);
  69
  70     DPRINTF("accepted migration\n");
  71
  72     if (c < 0) {
  73         error_report("could not accept migration connection (%s)",
  74                      strerror(errno));
  75         return;
  76     }
  77
  78     f = qemu_fopen_socket(c, "rb");
  79     if (f == NULL) {
  80         error_report("could not qemu_fopen socket");
  81         goto out;
  82     }
  83
  84     process_incoming_migration(f);
  85     return;
  86
  87 out:
  88     closesocket(c);
  89 }
  90
  91 void tcp_start_incoming_migration(const char *host_port, Error **errp)
  92 {
  93     int s;
  94
  95     s = inet_listen(host_port, NULL, 256, SOCK_STREAM, 0, errp);
  96     if (s < 0) {
  97         return;
  98     }
  99
 100     qemu_set_fd_handler(s, tcp_accept_incoming_migration, NULL,
 101                         (void *)(intptr_t)s);
 102 }