This patch introduces a tcp protocol for live migration. It can be used as follows:
qemu-system-x86_64 -hda ~/images/linux-test.img -monitor stdio <vm runs for a while> (qemu) migrate tcp:localhost:1025 On the same system: qemu-system-x86_64 -hda ~/images/linux-test.img -incoming tcp:localhost:1025 The monitor can be interacted with while waiting for an incoming live migration. Signed-off-by: Anthony Liguori <[EMAIL PROTECTED]> diff --git a/Makefile.target b/Makefile.target index 6bf5229..0fa585c 100644 --- a/Makefile.target +++ b/Makefile.target @@ -473,7 +473,7 @@ endif #CONFIG_DARWIN_USER ifndef CONFIG_USER_ONLY OBJS=vl.o osdep.o monitor.o pci.o loader.o isa_mmio.o machine.o net-checksum.o -OBJS+=migration.o +OBJS+=migration.o migration-tcp.o ifdef CONFIG_WIN32 OBJS+=block-raw-win32.o else diff --git a/migration-tcp.c b/migration-tcp.c new file mode 100644 index 0000000..6b46bd4 --- /dev/null +++ b/migration-tcp.c @@ -0,0 +1,243 @@ +#include "qemu-common.h" +#include "qemu_socket.h" +#include "migration.h" +#include "qemu-char.h" +#include "sysemu.h" +#include "console.h" + +/* FIXME resume monitor on error */ + + +typedef struct FdMigrationState +{ + QEMUFile *file; + int64_t bandwidth_limit; + int fd; +} FdMigrationState; + +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; + return close(s->fd); +} + +static void fd_wait_for_unfreeze(void *opaque) +{ + FdMigrationState *s = opaque; + int ret; + + 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 (qemu_savevm_state_iterate(s->file) == 1) { + vm_stop(0); + qemu_savevm_state_complete(s->file); + qemu_fclose(s->file); + qemu_free(s); + monitor_resume(); + } +} + +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); + + ret = qemu_savevm_state_begin(s->file); + if (ret < 0) { + fprintf(stderr, "savevm failed %d\n", ret); + return; + } + + monitor_suspend(); + + fd_put_ready(s); +} + +static void tcp_wait_for_connect(void *opaque) +{ + FdMigrationState *s = opaque; + int val, ret; + int valsize = sizeof(val); + + do { + ret = getsockopt(s->fd, SOL_SOCKET, SO_ERROR, &val, &valsize); + } while (ret == -1 && errno == EINTR); + + if (ret < 0) { + fprintf(stderr, "Could not query connect success\n"); + return; + } + + qemu_set_fd_handler2(s->fd, NULL, NULL, NULL, NULL); + + if (val == 0) + tcp_connect_migrate(s); + else { + fprintf(stderr, "failed to connect to host\n"); + close(s->fd); + qemu_free(s); + } +} + +int tcp_start_outgoing_migration(const char *host_port, int64_t bandwidth_limit) +{ + struct sockaddr_in addr; + FdMigrationState *s; + int ret; + + if (parse_host_port(&addr, host_port) < 0) { + fprintf(stderr, "invalid host/port combination: %s\n", host_port); + return -EINVAL; + } + + s = qemu_mallocz(sizeof(*s)); + if (s == NULL) + return -ENOMEM; + + s->bandwidth_limit = bandwidth_limit; + s->fd = socket(PF_INET, SOCK_STREAM, 0); + if (s->fd == -1) { + qemu_free(s); + return -errno; + } + + fcntl(s->fd, F_SETFL, O_NONBLOCK); + + 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) { + fprintf(stderr, "failed to connect to host\n"); + close(s->fd); + qemu_free(s); + } else if (ret >= 0) + tcp_connect_migrate(s); + + return 0; +} + +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); + + 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; + } + + /* 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; +} diff --git a/migration.c b/migration.c index 8a8b4a5..6023e02 100644 --- a/migration.c +++ b/migration.c @@ -200,10 +200,20 @@ QEMUFile *qemu_fopen_ops_buffered(void *opaque, void qemu_start_incoming_migration(const char *uri) { - fprintf(stderr, "unknown migration protocol: %s\n", uri); + const char *p; + + if (strstart(uri, "tcp:", &p)) + tcp_start_incoming_migration(p); + else + fprintf(stderr, "unknown migration protocol: %s\n", uri); } void do_migrate(const char *uri) { - fprintf(stderr, "unknown migration protocol: %s\n", uri); + const char *p; + + if (strstart(uri, "tcp:", &p)) + tcp_start_outgoing_migration(p, 20 << 20); + else + fprintf(stderr, "unknown migration protocol: %s\n", uri); } diff --git a/migration.h b/migration.h index 2119a59..314cc87 100644 --- a/migration.h +++ b/migration.h @@ -18,4 +18,8 @@ void qemu_start_incoming_migration(const char *uri); void do_migrate(const char *uri); +int tcp_start_incoming_migration(const char *host_port); + +int tcp_start_outgoing_migration(const char *host_port, int64_t bandwidth_limit); + #endif -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html