diff options
Diffstat (limited to 'migration-tcp.c')
| -rw-r--r-- | migration-tcp.c | 371 |
1 files changed, 371 insertions, 0 deletions
diff --git a/migration-tcp.c b/migration-tcp.c new file mode 100644 index 000000000..df8080fe7 --- /dev/null +++ b/migration-tcp.c @@ -0,0 +1,371 @@ +/* + * 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. + * + */ + +#include "qemu-common.h" +#include "qemu_socket.h" +#include "migration.h" +#include "qemu-char.h" +#include "sysemu.h" +#include "console.h" +#include "buffered_file.h" +#include "block.h" + +//#define DEBUG_MIGRATION_TCP + +typedef struct FdMigrationState +{ + MigrationState mig_state; + QEMUFile *file; + int64_t bandwidth_limit; + int fd; + int detach; + int state; +} FdMigrationState; + +#ifdef DEBUG_MIGRATION_TCP +#define dprintf(fmt, ...) \ + do { printf("migration-tcp: " fmt, ## __VA_ARGS__); } while (0) +#else +#define dprintf(fmt, ...) \ + do { } while (0) +#endif + +int debug_me = 0; + +static void tcp_cleanup(FdMigrationState *s) +{ + if (s->detach == 2) { + monitor_resume(); + s->detach = 0; + } + + qemu_set_fd_handler2(s->fd, NULL, NULL, NULL, NULL); + + if (s->file) { + debug_me = 1; + dprintf("closing file\n"); + qemu_fclose(s->file); + } + + if (s->fd != -1) + close(s->fd); + + s->fd = -1; +} + +static void tcp_error(FdMigrationState *s) +{ + dprintf("setting error state\n"); + s->state = MIG_STATE_ERROR; + tcp_cleanup(s); +} + +static void fd_put_notify(void *opaque) +{ + FdMigrationState *s = opaque; + + qemu_set_fd_handler2(s->fd, NULL, NULL, NULL, NULL); + qemu_file_put_notify(s->file); +} + +static ssize_t fd_put_buffer(void *opaque, const void *data, size_t size) +{ + FdMigrationState *s = opaque; + ssize_t ret; + + do { + ret = write(s->fd, data, size); + } while (ret == -1 && errno == EINTR); + + if (ret == -1) + ret = -errno; + + if (ret == -EAGAIN) + qemu_set_fd_handler2(s->fd, NULL, NULL, fd_put_notify, s); + + return ret; +} + +static int fd_close(void *opaque) +{ + FdMigrationState *s = opaque; + dprintf("fd_close\n"); + if (s->fd != -1) { + close(s->fd); + s->fd = -1; + } + return 0; +} + +static void fd_wait_for_unfreeze(void *opaque) +{ + FdMigrationState *s = opaque; + int ret; + + dprintf("wait for unfreeze\n"); + if (s->state != MIG_STATE_ACTIVE) + return; + + do { + fd_set wfds; + + FD_ZERO(&wfds); + FD_SET(s->fd, &wfds); + + ret = select(s->fd + 1, NULL, &wfds, NULL, NULL); + } while (ret == -1 && errno == EINTR); +} + +static void fd_put_ready(void *opaque) +{ + FdMigrationState *s = opaque; + + if (s->state != MIG_STATE_ACTIVE) { + dprintf("put_ready returning because of non-active state\n"); + return; + } + + dprintf("iterate\n"); + if (qemu_savevm_state_iterate(s->file) == 1) { + dprintf("done iterating\n"); + vm_stop(0); + + bdrv_flush_all(); + qemu_savevm_state_complete(s->file); + s->state = MIG_STATE_COMPLETED; + tcp_cleanup(s); + } +} + +static void tcp_connect_migrate(FdMigrationState *s) +{ + int ret; + + s->file = qemu_fopen_ops_buffered(s, + s->bandwidth_limit, + fd_put_buffer, + fd_put_ready, + fd_wait_for_unfreeze, + fd_close); + + dprintf("beginning savevm\n"); + ret = qemu_savevm_state_begin(s->file); + if (ret < 0) { + dprintf("failed, %d\n", ret); + tcp_error(s); + return; + } + + fd_put_ready(s); +} + +static void tcp_wait_for_connect(void *opaque) +{ + FdMigrationState *s = opaque; + int val, ret; + int valsize = sizeof(val); + + dprintf("connect completed\n"); + do { + ret = getsockopt(s->fd, SOL_SOCKET, SO_ERROR, &val, &valsize); + } while (ret == -1 && errno == EINTR); + + if (ret < 0) { + tcp_error(s); + return; + } + + qemu_set_fd_handler2(s->fd, NULL, NULL, NULL, NULL); + + if (val == 0) + tcp_connect_migrate(s); + else { + dprintf("error connecting %d\n", val); + tcp_error(s); + } +} + +static FdMigrationState *to_fms(MigrationState *mig_state) +{ + return container_of(mig_state, FdMigrationState, mig_state); +} + +static int tcp_get_status(MigrationState *mig_state) +{ + FdMigrationState *s = to_fms(mig_state); + + return s->state; +} + +static void tcp_cancel(MigrationState *mig_state) +{ + FdMigrationState *s = to_fms(mig_state); + + if (s->state != MIG_STATE_ACTIVE) + return; + + dprintf("cancelling migration\n"); + + s->state = MIG_STATE_CANCELLED; + + tcp_cleanup(s); +} + +static void tcp_release(MigrationState *mig_state) +{ + FdMigrationState *s = to_fms(mig_state); + + dprintf("releasing state\n"); + + if (s->state == MIG_STATE_ACTIVE) { + s->state = MIG_STATE_CANCELLED; + tcp_cleanup(s); + } + free(s); +} + +MigrationState *tcp_start_outgoing_migration(const char *host_port, + int64_t bandwidth_limit, + int async) +{ + struct sockaddr_in addr; + FdMigrationState *s; + int ret; + + if (parse_host_port(&addr, host_port) < 0) + return NULL; + + s = qemu_mallocz(sizeof(*s)); + if (s == NULL) + return NULL; + + s->mig_state.cancel = tcp_cancel; + s->mig_state.get_status = tcp_get_status; + s->mig_state.release = tcp_release; + + s->state = MIG_STATE_ACTIVE; + s->detach = !async; + s->bandwidth_limit = bandwidth_limit; + s->fd = socket(PF_INET, SOCK_STREAM, 0); + if (s->fd == -1) { + qemu_free(s); + return NULL; + } + + fcntl(s->fd, F_SETFL, O_NONBLOCK); + + if (s->detach == 1) { + dprintf("detaching from monitor\n"); + monitor_suspend(); + s->detach = 2; + } + + do { + ret = connect(s->fd, (struct sockaddr *)&addr, sizeof(addr)); + if (ret == -1) + ret = -errno; + + if (ret == -EINPROGRESS) + qemu_set_fd_handler2(s->fd, NULL, NULL, tcp_wait_for_connect, s); + } while (ret == -EINTR); + + if (ret < 0 && ret != -EINPROGRESS) { + dprintf("connect failed\n"); + close(s->fd); + qemu_free(s); + s = NULL; + } else if (ret >= 0) + tcp_connect_migrate(s); + + return &s->mig_state; +} + +static void tcp_accept_incoming_migration(void *opaque) +{ + struct sockaddr_in addr; + socklen_t addrlen = sizeof(addr); + int s = (unsigned long)opaque; + QEMUFile *f; + int c, ret; + + do { + c = accept(s, (struct sockaddr *)&addr, &addrlen); + } while (c == -1 && errno == EINTR); + + dprintf("accepted migration\n"); + + if (c == -1) { + fprintf(stderr, "could not accept migration connection\n"); + return; + } + + f = qemu_fopen_fd(c); + if (f == NULL) { + fprintf(stderr, "could not qemu_fopen socket\n"); + goto out; + } + + vm_stop(0); /* just in case */ + ret = qemu_loadvm_state(f); + if (ret < 0) { + fprintf(stderr, "load of migration failed\n"); + goto out_fopen; + } + qemu_announce_self(); + dprintf("successfully loaded vm state\n"); + + /* we've successfully migrated, close the server socket */ + qemu_set_fd_handler2(s, NULL, NULL, NULL, NULL); + close(s); + + vm_start(); + +out_fopen: + qemu_fclose(f); +out: + close(c); +} + +int tcp_start_incoming_migration(const char *host_port) +{ + struct sockaddr_in addr; + int val; + int s; + + if (parse_host_port(&addr, host_port) < 0) { + fprintf(stderr, "invalid host/port combination: %s\n", host_port); + return -EINVAL; + } + + s = socket(PF_INET, SOCK_STREAM, 0); + if (s == -1) + return -errno; + + 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 *)(unsigned long)s); + + return 0; + +err: + close(s); + return -errno; +} |