qemu/migration-exec.c

143 lines
3.2 KiB
C

/*
* QEMU live migration
*
* Copyright IBM, Corp. 2008
* Copyright Dell MessageOne 2008
*
* Authors:
* Anthony Liguori <aliguori@us.ibm.com>
* Charles Duffy <charles_duffy@messageone.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 "qemu-char.h"
#include "sysemu.h"
#include "buffered_file.h"
#include "block.h"
//#define DEBUG_MIGRATION_EXEC
#ifdef DEBUG_MIGRATION_EXEC
#define dprintf(fmt, ...) \
do { printf("migration-exec: " fmt, ## __VA_ARGS__); } while (0)
#else
#define dprintf(fmt, ...) \
do { } while (0)
#endif
static int file_errno(FdMigrationState *s)
{
return errno;
}
static int file_write(FdMigrationState *s, const void * buf, size_t size)
{
return write(s->fd, buf, size);
}
static int exec_close(FdMigrationState *s)
{
dprintf("exec_close\n");
if (s->opaque) {
qemu_fclose(s->opaque);
s->opaque = NULL;
s->fd = -1;
}
return 0;
}
MigrationState *exec_start_outgoing_migration(const char *command,
int64_t bandwidth_limit,
int detach)
{
FdMigrationState *s;
FILE *f;
s = qemu_mallocz(sizeof(*s));
f = popen(command, "w");
if (f == NULL) {
dprintf("Unable to popen exec target\n");
goto err_after_alloc;
}
s->fd = fileno(f);
if (s->fd == -1) {
dprintf("Unable to retrieve file descriptor for popen'd handle\n");
goto err_after_open;
}
if (fcntl(s->fd, F_SETFD, O_NONBLOCK) == -1) {
dprintf("Unable to set nonblocking mode on file descriptor\n");
goto err_after_open;
}
s->opaque = qemu_popen(f, "w");
s->close = exec_close;
s->get_error = file_errno;
s->write = file_write;
s->mig_state.cancel = migrate_fd_cancel;
s->mig_state.get_status = migrate_fd_get_status;
s->mig_state.release = migrate_fd_release;
s->state = MIG_STATE_ACTIVE;
s->mon_resume = NULL;
s->bandwidth_limit = bandwidth_limit;
if (!detach)
migrate_fd_monitor_suspend(s);
migrate_fd_connect(s);
return &s->mig_state;
err_after_open:
pclose(f);
err_after_alloc:
qemu_free(s);
return NULL;
}
static void exec_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_popen_fd(f), NULL, NULL, NULL, NULL);
err:
qemu_fclose(f);
}
int exec_start_incoming_migration(const char *command)
{
QEMUFile *f;
dprintf("Attempting to start an incoming migration\n");
f = qemu_popen_cmd(command, "r");
if(f == NULL) {
dprintf("Unable to apply qemu wrapper to popen file\n");
return -errno;
}
qemu_set_fd_handler2(qemu_popen_fd(f), NULL,
exec_accept_incoming_migration, NULL,
(void *)(unsigned long)f);
return 0;
}