migration/unix.c

   1 /*
   2  * QEMU live migration via Unix Domain Sockets
   3  *
   4  * Copyright Red Hat, Inc. 2009-2016
   5  *
   6  * Authors:
   7  *  Chris Lalancette <clalance@redhat.com>
   8  *  Daniel P. Berrange <berrange@redhat.com>
   9  *
  10  * This work is licensed under the terms of the GNU GPL, version 2.  See
  11  * the COPYING file in the top-level directory.
  12  *
  13  * Contributions after 2012-01-13 are licensed under the terms of the
  14  * GNU GPL, version 2 or (at your option) any later version.
  15  */
  16
  17 #include "qemu/osdep.h"
  18
  19 #include "qemu-common.h"
  20 #include "qemu/error-report.h"
  21 #include "qapi/error.h"
  22 #include "migration/migration.h"
  23 #include "migration/qemu-file.h"
  24 #include "io/channel-socket.h"
  25 #include "trace.h"
  26
  27
  28 static SocketAddress *unix_build_address(const char *path)
  29 {
  30     SocketAddress *saddr;
  31
  32     saddr = g_new0(SocketAddress, 1);
  33     saddr->type = SOCKET_ADDRESS_KIND_UNIX;
  34     saddr->u.q_unix.data = g_new0(UnixSocketAddress, 1);
  35     saddr->u.q_unix.data->path = g_strdup(path);
  36
  37     return saddr;
  38 }
  39
  40
  41 static void unix_outgoing_migration(Object *src,
  42                                     Error *err,
  43                                     gpointer opaque)
  44 {
  45     MigrationState *s = opaque;
  46     QIOChannel *sioc = QIO_CHANNEL(src);
  47
  48     if (err) {
  49         trace_migration_unix_outgoing_error(error_get_pretty(err));
  50         s->to_dst_file = NULL;
  51         migrate_fd_error(s, err);
  52     } else {
  53         trace_migration_unix_outgoing_connected();
  54         migration_set_outgoing_channel(s, sioc);
  55     }
  56     object_unref(src);
  57 }
  58
  59
  60 void unix_start_outgoing_migration(MigrationState *s, const char *path, Error **errp)
  61 {
  62     SocketAddress *saddr = unix_build_address(path);
  63     QIOChannelSocket *sioc;
  64     sioc = qio_channel_socket_new();
  65     qio_channel_socket_connect_async(sioc,
  66                                      saddr,
  67                                      unix_outgoing_migration,
  68                                      s,
  69                                      NULL);
  70     qapi_free_SocketAddress(saddr);
  71 }
  72
  73
  74 static gboolean unix_accept_incoming_migration(QIOChannel *ioc,
  75                                                GIOCondition condition,
  76                                                gpointer opaque)
  77 {
  78     QIOChannelSocket *sioc;
  79     Error *err = NULL;
  80
  81     sioc = qio_channel_socket_accept(QIO_CHANNEL_SOCKET(ioc),
  82                                      &err);
  83     if (!sioc) {
  84         error_report("could not accept migration connection (%s)",
  85                      error_get_pretty(err));
  86         goto out;
  87     }
  88
  89     trace_migration_unix_incoming_accepted();
  90
  91     migration_set_incoming_channel(migrate_get_current(),
  92                                    QIO_CHANNEL(sioc));
  93     object_unref(OBJECT(sioc));
  94
  95 out:
  96     /* Close listening socket as its no longer needed */
  97     qio_channel_close(ioc, NULL);
  98     return FALSE; /* unregister */
  99 }
 100
 101
 102 void unix_start_incoming_migration(const char *path, Error **errp)
 103 {
 104     SocketAddress *saddr = unix_build_address(path);
 105     QIOChannelSocket *listen_ioc;
 106
 107     listen_ioc = qio_channel_socket_new();
 108     if (qio_channel_socket_listen_sync(listen_ioc, saddr, errp) < 0) {
 109         object_unref(OBJECT(listen_ioc));
 110         qapi_free_SocketAddress(saddr);
 111         return;
 112     }
 113
 114     qio_channel_add_watch(QIO_CHANNEL(listen_ioc),
 115                           G_IO_IN,
 116                           unix_accept_incoming_migration,
 117                           listen_ioc,
 118                           (GDestroyNotify)object_unref);
 119
 120     qapi_free_SocketAddress(saddr);
 121 }