qemu/migration-tcp.c

195 lines
4.2 KiB
C

/*
* QEMU live migration
*
* Copyright IBM, Corp. 2008
*
* Authors:
* Anthony Liguori <aliguori@us.ibm.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_socket.h"
#include "migration.h"
#include "qemu-char.h"
#include "buffered_file.h"
#include "block.h"
//#define DEBUG_MIGRATION_TCP
#ifdef DEBUG_MIGRATION_TCP
#define DPRINTF(fmt, ...) \
do { printf("migration-tcp: " fmt, ## __VA_ARGS__); } while (0)
#else
#define DPRINTF(fmt, ...) \
do { } while (0)
#endif
static int socket_errno(MigrationState *s)
{
return socket_error();
}
static int socket_write(MigrationState *s, const void * buf, size_t size)
{
return send(s->fd, buf, size, 0);
}
static int tcp_close(MigrationState *s)
{
int r = 0;
DPRINTF("tcp_close\n");
if (s->fd != -1) {
if (close(s->fd) < 0) {
r = -errno;
}
s->fd = -1;
}
return r;
}
static void tcp_wait_for_connect(void *opaque)
{
MigrationState *s = opaque;
int val, ret;
socklen_t valsize = sizeof(val);
DPRINTF("connect completed\n");
do {
ret = getsockopt(s->fd, SOL_SOCKET, SO_ERROR, (void *) &val, &valsize);
} while (ret == -1 && (socket_error()) == EINTR);
if (ret < 0) {
migrate_fd_error(s);
return;
}
qemu_set_fd_handler2(s->fd, NULL, NULL, NULL, NULL);
if (val == 0)
migrate_fd_connect(s);
else {
DPRINTF("error connecting %d\n", val);
migrate_fd_error(s);
}
}
int tcp_start_outgoing_migration(MigrationState *s, const char *host_port)
{
struct sockaddr_in addr;
int ret;
ret = parse_host_port(&addr, host_port);
if (ret < 0) {
return ret;
}
s->get_error = socket_errno;
s->write = socket_write;
s->close = tcp_close;
s->fd = qemu_socket(PF_INET, SOCK_STREAM, 0);
if (s->fd == -1) {
DPRINTF("Unable to open socket");
return -socket_error();
}
socket_set_nonblock(s->fd);
do {
ret = connect(s->fd, (struct sockaddr *)&addr, sizeof(addr));
if (ret == -1) {
ret = -socket_error();
}
if (ret == -EINPROGRESS || ret == -EWOULDBLOCK) {
qemu_set_fd_handler2(s->fd, NULL, NULL, tcp_wait_for_connect, s);
return 0;
}
} while (ret == -EINTR);
if (ret < 0) {
DPRINTF("connect failed\n");
migrate_fd_error(s);
return ret;
}
migrate_fd_connect(s);
return 0;
}
static void tcp_accept_incoming_migration(void *opaque)
{
struct sockaddr_in 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 && socket_error() == EINTR);
DPRINTF("accepted migration\n");
if (c == -1) {
fprintf(stderr, "could not accept migration connection\n");
goto out2;
}
f = qemu_fopen_socket(c);
if (f == NULL) {
fprintf(stderr, "could not qemu_fopen socket\n");
goto out;
}
process_incoming_migration(f);
qemu_fclose(f);
out:
close(c);
out2:
qemu_set_fd_handler2(s, NULL, NULL, NULL, NULL);
close(s);
}
int tcp_start_incoming_migration(const char *host_port)
{
struct sockaddr_in addr;
int val;
int s;
DPRINTF("Attempting to start an incoming migration\n");
if (parse_host_port(&addr, host_port) < 0) {
fprintf(stderr, "invalid host/port combination: %s\n", host_port);
return -EINVAL;
}
s = qemu_socket(PF_INET, SOCK_STREAM, 0);
if (s == -1) {
return -socket_error();
}
val = 1;
setsockopt(s, SOL_SOCKET, SO_REUSEADDR, (const char *)&val, sizeof(val));
if (bind(s, (struct sockaddr *)&addr, sizeof(addr)) == -1) {
goto err;
}
if (listen(s, 1) == -1) {
goto err;
}
qemu_set_fd_handler2(s, NULL, tcp_accept_incoming_migration, NULL,
(void *)(intptr_t)s);
return 0;
err:
close(s);
return -socket_error();
}