qemu/migration-unix.c

122 lines
2.6 KiB
C

/*
* QEMU live migration via Unix Domain Sockets
*
* 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.
*
* Contributions after 2012-01-13 are licensed under the terms of the
* GNU GPL, version 2 or (at your option) any later version.
*/
#include "qemu-common.h"
#include "qemu/sockets.h"
#include "migration/migration.h"
#include "migration/qemu-file.h"
#include "block/block.h"
//#define DEBUG_MIGRATION_UNIX
#ifdef DEBUG_MIGRATION_UNIX
#define DPRINTF(fmt, ...) \
do { printf("migration-unix: " fmt, ## __VA_ARGS__); } while (0)
#else
#define DPRINTF(fmt, ...) \
do { } while (0)
#endif
static int unix_errno(MigrationState *s)
{
return errno;
}
static int unix_write(MigrationState *s, const void * buf, size_t size)
{
return write(s->fd, buf, size);
}
static int unix_close(MigrationState *s)
{
int r = 0;
DPRINTF("unix_close\n");
if (close(s->fd) < 0) {
r = -errno;
}
return r;
}
static void unix_wait_for_connect(int fd, void *opaque)
{
MigrationState *s = opaque;
if (fd < 0) {
DPRINTF("migrate connect error\n");
s->fd = -1;
migrate_fd_error(s);
} else {
DPRINTF("migrate connect success\n");
s->fd = fd;
migrate_fd_connect(s);
}
}
void unix_start_outgoing_migration(MigrationState *s, const char *path, Error **errp)
{
s->get_error = unix_errno;
s->write = unix_write;
s->close = unix_close;
s->fd = unix_nonblocking_connect(path, unix_wait_for_connect, s, errp);
}
static void unix_accept_incoming_migration(void *opaque)
{
struct sockaddr_un addr;
socklen_t addrlen = sizeof(addr);
int s = (intptr_t)opaque;
QEMUFile *f;
int c;
do {
c = qemu_accept(s, (struct sockaddr *)&addr, &addrlen);
} while (c == -1 && errno == EINTR);
qemu_set_fd_handler2(s, NULL, NULL, NULL, NULL);
close(s);
DPRINTF("accepted migration\n");
if (c == -1) {
fprintf(stderr, "could not accept migration connection\n");
goto out;
}
f = qemu_fopen_socket(c);
if (f == NULL) {
fprintf(stderr, "could not qemu_fopen socket\n");
goto out;
}
process_incoming_migration(f);
return;
out:
close(c);
}
void unix_start_incoming_migration(const char *path, Error **errp)
{
int s;
s = unix_listen(path, NULL, 0, errp);
if (s < 0) {
return;
}
qemu_set_fd_handler2(s, NULL, unix_accept_incoming_migration, NULL,
(void *)(intptr_t)s);
}