/* * 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; vm_stop(0); /* just in case */ 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); vm_start(); 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; }