LXR qemu/migration/fd.c

   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 "channel.h"
  19#include "fd.h"
  20#include "file.h"
  21#include "migration.h"
  22#include "monitor/monitor.h"
  23#include "qemu/error-report.h"
  24#include "qemu/sockets.h"
  25#include "io/channel-util.h"
  26#include "trace.h"
  27
  28static bool fd_is_pipe(int fd)
  29{
  30    struct stat statbuf;
  31
  32    if (fstat(fd, &statbuf) == -1) {
  33        return false;
  34    }
  35
  36    return S_ISFIFO(statbuf.st_mode);
  37}
  38
  39static bool migration_fd_valid(int fd)
  40{
  41    if (fd_is_socket(fd)) {
  42        return true;
  43    }
  44
  45    if (fd_is_pipe(fd)) {
  46        return true;
  47    }
  48
  49    return false;
  50}
  51
  52void fd_start_outgoing_migration(MigrationState *s, const char *fdname, Error **errp)
  53{
  54    QIOChannel *ioc;
  55    int fd = monitor_get_fd(monitor_cur(), fdname, errp);
  56    if (fd == -1) {
  57        return;
  58    }
  59
  60    if (!migration_fd_valid(fd)) {
  61        warn_report("fd: migration to a file is deprecated."
  62                    " Use file: instead.");
  63    }
  64
  65    trace_migration_fd_outgoing(fd);
  66    ioc = qio_channel_new_fd(fd, errp);
  67    if (!ioc) {
  68        close(fd);
  69        return;
  70    }
  71
  72    qio_channel_set_name(ioc, "migration-fd-outgoing");
  73    migration_channel_connect(s, ioc, NULL, NULL);
  74    object_unref(OBJECT(ioc));
  75}
  76
  77static gboolean fd_accept_incoming_migration(QIOChannel *ioc,
  78                                             GIOCondition condition,
  79                                             gpointer opaque)
  80{
  81    migration_channel_process_incoming(ioc);
  82    object_unref(OBJECT(ioc));
  83    return G_SOURCE_REMOVE;
  84}
  85
  86void fd_start_incoming_migration(const char *fdname, Error **errp)
  87{
  88    QIOChannel *ioc;
  89    int fd = monitor_fd_param(monitor_cur(), fdname, errp);
  90    if (fd == -1) {
  91        return;
  92    }
  93
  94    if (!migration_fd_valid(fd)) {
  95        warn_report("fd: migration to a file is deprecated."
  96                    " Use file: instead.");
  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    qio_channel_set_name(ioc, "migration-fd-incoming");
 108    qio_channel_add_watch_full(ioc, G_IO_IN,
 109                               fd_accept_incoming_migration,
 110                               NULL, NULL,
 111                               g_main_context_get_thread_default());
 112}
 113