qemu/migration-fd.c

144 lines
3.1 KiB
C

/*
* QEMU live migration via generic fd
*
* Copyright Red Hat, Inc. 2009
*
* Authors:
* Chris Lalancette <clalance@redhat.com>
*
* This work is licensed under the terms of the GNU GPL, version 2. See
* the COPYING file in the top-level directory.
*
*/
#include "qemu-common.h"
#include "qemu_socket.h"
#include "migration.h"
#include "monitor.h"
#include "qemu-char.h"
#include "sysemu.h"
#include "buffered_file.h"
#include "block.h"
#include "qemu_socket.h"
//#define DEBUG_MIGRATION_FD
#ifdef DEBUG_MIGRATION_FD
#define dprintf(fmt, ...) \
do { printf("migration-fd: " fmt, ## __VA_ARGS__); } while (0)
#else
#define dprintf(fmt, ...) \
do { } while (0)
#endif
static int fd_errno(FdMigrationState *s)
{
return errno;
}
static int fd_write(FdMigrationState *s, const void * buf, size_t size)
{
return write(s->fd, buf, size);
}
static int fd_close(FdMigrationState *s)
{
dprintf("fd_close\n");
if (s->fd != -1) {
close(s->fd);
s->fd = -1;
}
return 0;
}
MigrationState *fd_start_outgoing_migration(Monitor *mon,
const char *fdname,
int64_t bandwidth_limit,
int detach,
int blk,
int inc)
{
FdMigrationState *s;
s = qemu_mallocz(sizeof(*s));
s->fd = monitor_get_fd(mon, fdname);
if (s->fd == -1) {
dprintf("fd_migration: invalid file descriptor identifier\n");
goto err_after_alloc;
}
if (fcntl(s->fd, F_SETFL, O_NONBLOCK) == -1) {
dprintf("Unable to set nonblocking mode on file descriptor\n");
goto err_after_open;
}
s->get_error = fd_errno;
s->write = fd_write;
s->close = fd_close;
s->mig_state.cancel = migrate_fd_cancel;
s->mig_state.get_status = migrate_fd_get_status;
s->mig_state.release = migrate_fd_release;
s->mig_state.blk = blk;
s->mig_state.shared = inc;
s->state = MIG_STATE_ACTIVE;
s->mon = NULL;
s->bandwidth_limit = bandwidth_limit;
if (!detach) {
migrate_fd_monitor_suspend(s, mon);
}
migrate_fd_connect(s);
return &s->mig_state;
err_after_open:
close(s->fd);
err_after_alloc:
qemu_free(s);
return NULL;
}
static void fd_accept_incoming_migration(void *opaque)
{
QEMUFile *f = opaque;
int ret;
ret = qemu_loadvm_state(f);
if (ret < 0) {
fprintf(stderr, "load of migration failed\n");
goto err;
}
qemu_announce_self();
dprintf("successfully loaded vm state\n");
/* we've successfully migrated, close the fd */
qemu_set_fd_handler2(qemu_stdio_fd(f), NULL, NULL, NULL, NULL);
if (autostart)
vm_start();
err:
qemu_fclose(f);
}
int fd_start_incoming_migration(const char *infd)
{
int fd;
QEMUFile *f;
dprintf("Attempting to start an incoming migration via fd\n");
fd = strtol(infd, NULL, 0);
f = qemu_fdopen(fd, "rb");
if(f == NULL) {
dprintf("Unable to apply qemu wrapper to file descriptor\n");
return -errno;
}
qemu_set_fd_handler2(fd, NULL, fd_accept_incoming_migration, NULL,
(void *)(unsigned long)f);
return 0;
}