From 065e281356282f59386272aa50590b566a1809d9 Mon Sep 17 00:00:00 2001 From: aliguori Date: Tue, 11 Nov 2008 16:46:33 +0000 Subject: Reintroduce migrate-to-exec: support (Charles Duffy) KVM's live migration support included support for exec: URLs, allowing system state to be written or received via an arbitrary popen()ed subprocess. This provides a convenient way to pipe state through a compression algorithm or an arbitrary network transport on its way to its destination, and a convenient way to write state to disk; libvirt's qemu driver currently uses migration to exec: targets for this latter purpose. This version of the patch refactors now-common code from migrate-tcp.c into migrate.c. Signed-off-by: Charles Duffy Signed-off-by: Anthony Liguori git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@5694 c046a42c-6fe2-441c-8c8c-71466251a162 --- migration-tcp.c | 188 ++++++-------------------------------------------------- 1 file changed, 18 insertions(+), 170 deletions(-) (limited to 'migration-tcp.c') diff --git a/migration-tcp.c b/migration-tcp.c index f13dc0da7d..100644ba27 100644 --- a/migration-tcp.c +++ b/migration-tcp.c @@ -22,16 +22,6 @@ //#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) @@ -40,64 +30,19 @@ typedef struct FdMigrationState do { } while (0) #endif -static void tcp_cleanup(FdMigrationState *s) +static int socket_errno(FdMigrationState *s) { - qemu_set_fd_handler2(s->fd, NULL, NULL, NULL, NULL); - - if (s->file) { - dprintf("closing file\n"); - qemu_fclose(s->file); - } - - if (s->fd != -1) - close(s->fd); - - /* Don't resume monitor until we've flushed all of the buffers */ - if (s->detach == 2) { - monitor_resume(); - s->detach = 0; - } - - 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); + return (s->get_error(s)); } -static ssize_t fd_put_buffer(void *opaque, const void *data, size_t size) +static int socket_write(FdMigrationState *s, const void * buf, size_t size) { - FdMigrationState *s = opaque; - ssize_t ret; - - do { - ret = send(s->fd, data, size, 0); - } while (ret == -1 && (socket_error() == EINTR || socket_error() == EWOULDBLOCK)); - - if (ret == -1) - ret = -socket_error(); - - if (ret == -EAGAIN) - qemu_set_fd_handler2(s->fd, NULL, NULL, fd_put_notify, s); - - return ret; + return send(s->fd, buf, size, 0); } -static int fd_close(void *opaque) +static int tcp_close(FdMigrationState *s) { - FdMigrationState *s = opaque; - dprintf("fd_close\n"); + dprintf("tcp_close\n"); if (s->fd != -1) { close(s->fd); s->fd = -1; @@ -105,67 +50,6 @@ static int fd_close(void *opaque) 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 && socket_error() == 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) { @@ -176,60 +60,21 @@ static void tcp_wait_for_connect(void *opaque) dprintf("connect completed\n"); do { ret = getsockopt(s->fd, SOL_SOCKET, SO_ERROR, &val, &valsize); - } while (ret == -1 && socket_error() == EINTR); + } while (ret == -1 && (s->get_error(s)) == EINTR); if (ret < 0) { - tcp_error(s); + migrate_fd_error(s); return; } qemu_set_fd_handler2(s->fd, NULL, NULL, NULL, NULL); if (val == 0) - tcp_connect_migrate(s); + migrate_fd_connect(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); + migrate_fd_error(s); } - free(s); } MigrationState *tcp_start_outgoing_migration(const char *host_port, @@ -247,9 +92,12 @@ MigrationState *tcp_start_outgoing_migration(const char *host_port, 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->get_error = socket_errno; + s->write = socket_write; + s->close = tcp_close; + 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->detach = !async; @@ -271,7 +119,7 @@ MigrationState *tcp_start_outgoing_migration(const char *host_port, do { ret = connect(s->fd, (struct sockaddr *)&addr, sizeof(addr)); if (ret == -1) - ret = -socket_error(); + ret = -(s->get_error(s)); if (ret == -EINPROGRESS || ret == -EWOULDBLOCK) qemu_set_fd_handler2(s->fd, NULL, NULL, tcp_wait_for_connect, s); @@ -283,7 +131,7 @@ MigrationState *tcp_start_outgoing_migration(const char *host_port, qemu_free(s); return NULL; } else if (ret >= 0) - tcp_connect_migrate(s); + migrate_fd_connect(s); return &s->mig_state; } -- cgit v1.2.1