/* * QEMU live migration via generic fd * * 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_socket.h" #include "migration.h" #include "monitor.h" #include "qemu-char.h" #include "buffered_file.h" #include "block.h" #include "qemu_socket.h" //#define DEBUG_MIGRATION_FD #ifdef DEBUG_MIGRATION_FD #define DPRINTF(fmt, ...) \ do { printf("migration-fd: " fmt, ## __VA_ARGS__); } while (0) #else #define DPRINTF(fmt, ...) \ do { } while (0) #endif static int fd_errno(MigrationState *s) { return errno; } static int fd_write(MigrationState *s, const void * buf, size_t size) { return write(s->fd, buf, size); } static int fd_close(MigrationState *s) { struct stat st; int ret; DPRINTF("fd_close\n"); if (s->fd != -1) { ret = fstat(s->fd, &st); if (ret == 0 && S_ISREG(st.st_mode)) { /* * If the file handle is a regular file make sure the * data is flushed to disk before signaling success. */ ret = fsync(s->fd); if (ret != 0) { ret = -errno; perror("migration-fd: fsync"); return ret; } } ret = close(s->fd); s->fd = -1; if (ret != 0) { ret = -errno; perror("migration-fd: close"); return ret; } } return 0; } int fd_start_outgoing_migration(MigrationState *s, const char *fdname) { s->fd = monitor_get_fd(cur_mon, fdname, NULL); if (s->fd == -1) { DPRINTF("fd_migration: invalid file descriptor identifier\n"); goto err_after_get_fd; } if (fcntl(s->fd, F_SETFL, O_NONBLOCK) == -1) { DPRINTF("Unable to set nonblocking mode on file descriptor\n"); goto err_after_open; } s->get_error = fd_errno; s->write = fd_write; s->close = fd_close; migrate_fd_connect(s); return 0; err_after_open: close(s->fd); err_after_get_fd: return -1; } static void fd_accept_incoming_migration(void *opaque) { QEMUFile *f = opaque; process_incoming_migration(f); qemu_set_fd_handler2(qemu_stdio_fd(f), NULL, NULL, NULL, NULL); qemu_fclose(f); } int fd_start_incoming_migration(const char *infd) { int fd; QEMUFile *f; DPRINTF("Attempting to start an incoming migration via fd\n"); fd = strtol(infd, NULL, 0); f = qemu_fdopen(fd, "rb"); if(f == NULL) { DPRINTF("Unable to apply qemu wrapper to file descriptor\n"); return -errno; } qemu_set_fd_handler2(fd, NULL, fd_accept_incoming_migration, NULL, f); return 0; }