blob: f9de064f3b134dfe9a2128e9189d5565dd7f81e7 [file] [log] [blame]
/*
* QEMU live migration channel operations
*
* Copyright Red Hat, Inc. 2016
*
* Authors:
* Daniel P. Berrange <berrange@redhat.com>
*
* 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/osdep.h"
#include "channel.h"
#include "tls.h"
#include "migration.h"
#include "qemu-file.h"
#include "trace.h"
#include "qapi/error.h"
#include "io/channel-tls.h"
#include "io/channel-socket.h"
#include "qemu/yank.h"
#include "yank_functions.h"
/**
* @migration_channel_process_incoming - Create new incoming migration channel
*
* Notice that TLS is special. For it we listen in a listener socket,
* and then create a new client socket from the TLS library.
*
* @ioc: Channel to which we are connecting
*/
void migration_channel_process_incoming(QIOChannel *ioc)
{
MigrationState *s = migrate_get_current();
Error *local_err = NULL;
trace_migration_set_incoming_channel(
ioc, object_get_typename(OBJECT(ioc)));
if (migrate_channel_requires_tls_upgrade(ioc)) {
migration_tls_channel_process_incoming(s, ioc, &local_err);
} else {
migration_ioc_register_yank(ioc);
migration_ioc_process_incoming(ioc, &local_err);
}
if (local_err) {
error_report_err(local_err);
}
}
/**
* @migration_channel_connect - Create new outgoing migration channel
*
* @s: Current migration state
* @ioc: Channel to which we are connecting
* @hostname: Where we want to connect
* @error: Error indicating failure to connect, free'd here
*/
void migration_channel_connect(MigrationState *s,
QIOChannel *ioc,
const char *hostname,
Error *error)
{
trace_migration_set_outgoing_channel(
ioc, object_get_typename(OBJECT(ioc)), hostname, error);
if (!error) {
if (migrate_channel_requires_tls_upgrade(ioc)) {
migration_tls_channel_connect(s, ioc, hostname, &error);
if (!error) {
/* tls_channel_connect will call back to this
* function after the TLS handshake,
* so we mustn't call migrate_fd_connect until then
*/
return;
}
} else {
QEMUFile *f = qemu_file_new_output(ioc);
migration_ioc_register_yank(ioc);
qemu_mutex_lock(&s->qemu_file_lock);
s->to_dst_file = f;
qemu_mutex_unlock(&s->qemu_file_lock);
}
}
migrate_fd_connect(s, error);
error_free(error);
}
/**
* @migration_channel_read_peek - Peek at migration channel, without
* actually removing it from channel buffer.
*
* @ioc: the channel object
* @buf: the memory region to read data into
* @buflen: the number of bytes to read in @buf
* @errp: pointer to a NULL-initialized error object
*
* Returns 0 if successful, returns -1 and sets @errp if fails.
*/
int migration_channel_read_peek(QIOChannel *ioc,
const char *buf,
const size_t buflen,
Error **errp)
{
ssize_t len = 0;
struct iovec iov = { .iov_base = (char *)buf, .iov_len = buflen };
while (true) {
len = qio_channel_readv_full(ioc, &iov, 1, NULL, NULL,
QIO_CHANNEL_READ_FLAG_MSG_PEEK, errp);
if (len < 0 && len != QIO_CHANNEL_ERR_BLOCK) {
return -1;
}
if (len == 0) {
error_setg(errp, "Failed to peek at channel");
return -1;
}
if (len == buflen) {
break;
}
/* 1ms sleep. */
if (qemu_in_coroutine()) {
qemu_co_sleep_ns(QEMU_CLOCK_REALTIME, 1000000);
} else {
g_usleep(1000);
}
}
return 0;
}