1 /* 2 * QEMU live migration via generic fd 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 #include "qapi/error.h" 19 #include "channel.h" 20 #include "fd.h" 21 #include "file.h" 22 #include "migration.h" 23 #include "monitor/monitor.h" 24 #include "io/channel-file.h" 25 #include "io/channel-socket.h" 26 #include "io/channel-util.h" 27 #include "options.h" 28 #include "trace.h" 29 30 31 static struct FdOutgoingArgs { 32 int fd; 33 } outgoing_args; 34 35 int fd_args_get_fd(void) 36 { 37 return outgoing_args.fd; 38 } 39 40 void fd_cleanup_outgoing_migration(void) 41 { 42 if (outgoing_args.fd > 0) { 43 close(outgoing_args.fd); 44 outgoing_args.fd = -1; 45 } 46 } 47 48 void fd_start_outgoing_migration(MigrationState *s, const char *fdname, Error **errp) 49 { 50 QIOChannel *ioc; 51 int fd = monitor_get_fd(monitor_cur(), fdname, errp); 52 int newfd; 53 54 if (fd == -1) { 55 return; 56 } 57 58 trace_migration_fd_outgoing(fd); 59 ioc = qio_channel_new_fd(fd, errp); 60 if (!ioc) { 61 close(fd); 62 return; 63 } 64 65 /* 66 * This is dup()ed just to avoid referencing an fd that might 67 * be already closed by the iochannel. 68 */ 69 newfd = dup(fd); 70 if (newfd == -1) { 71 error_setg_errno(errp, errno, "Could not dup FD %d", fd); 72 object_unref(ioc); 73 return; 74 } 75 outgoing_args.fd = newfd; 76 77 qio_channel_set_name(ioc, "migration-fd-outgoing"); 78 migration_channel_connect(s, ioc, NULL, NULL); 79 object_unref(OBJECT(ioc)); 80 } 81 82 static gboolean fd_accept_incoming_migration(QIOChannel *ioc, 83 GIOCondition condition, 84 gpointer opaque) 85 { 86 migration_channel_process_incoming(ioc); 87 object_unref(OBJECT(ioc)); 88 return G_SOURCE_REMOVE; 89 } 90 91 void fd_start_incoming_migration(const char *fdname, Error **errp) 92 { 93 QIOChannel *ioc; 94 int fd = monitor_fd_param(monitor_cur(), fdname, errp); 95 if (fd == -1) { 96 return; 97 } 98 99 trace_migration_fd_incoming(fd); 100 101 ioc = qio_channel_new_fd(fd, errp); 102 if (!ioc) { 103 close(fd); 104 return; 105 } 106 107 if (migrate_multifd()) { 108 if (fd_is_socket(fd)) { 109 error_setg(errp, 110 "Multifd migration to a socket FD is not supported"); 111 object_unref(ioc); 112 return; 113 } 114 115 file_create_incoming_channels(ioc, errp); 116 } else { 117 qio_channel_set_name(ioc, "migration-fd-incoming"); 118 qio_channel_add_watch_full(ioc, G_IO_IN, 119 fd_accept_incoming_migration, 120 NULL, NULL, 121 g_main_context_get_thread_default()); 122 } 123 } 124