From 5ac1fad324d869ab6971256aa56188ebac784e46 Mon Sep 17 00:00:00 2001 From: Paolo Bonzini Date: Tue, 18 Aug 2009 15:56:25 +0200 Subject: [PATCH] add file descriptor migration Signed-off-by: Paolo Bonzini Cc: Chris Lalancette Signed-off-by: Anthony Liguori --- Makefile | 2 +- hw/hw.h | 1 + migration-fd.c | 137 +++++++++++++++++++++++++++++++++++++++++++++++++ migration.c | 4 ++ migration.h | 7 +++ savevm.c | 28 ++++++++++ 6 files changed, 178 insertions(+), 1 deletion(-) create mode 100644 migration-fd.c diff --git a/Makefile b/Makefile index e2ea91d300..b0a84f36e4 100644 --- a/Makefile +++ b/Makefile @@ -93,7 +93,7 @@ obj-y += qdev.o qdev-properties.o ssi.o obj-$(CONFIG_BRLAPI) += baum.o obj-$(CONFIG_WIN32) += tap-win32.o -obj-$(CONFIG_POSIX) += migration-exec.o migration-unix.o +obj-$(CONFIG_POSIX) += migration-exec.o migration-unix.o migration-fd.o audio/audio.o audio/fmodaudio.o: QEMU_CFLAGS += $(FMOD_CFLAGS) diff --git a/hw/hw.h b/hw/hw.h index 322f077079..91bf800628 100644 --- a/hw/hw.h +++ b/hw/hw.h @@ -49,6 +49,7 @@ QEMUFile *qemu_fopen_ops(void *opaque, QEMUFilePutBufferFunc *put_buffer, QEMUFileRateLimit *rate_limit, QEMUFileSetRateLimit *set_rate_limit); QEMUFile *qemu_fopen(const char *filename, const char *mode); +QEMUFile *qemu_fdopen(int fd, const char *mode); QEMUFile *qemu_fopen_socket(int fd); QEMUFile *qemu_popen(FILE *popen_file, const char *mode); QEMUFile *qemu_popen_cmd(const char *command, const char *mode); diff --git a/migration-fd.c b/migration-fd.c new file mode 100644 index 0000000000..15b44158ff --- /dev/null +++ b/migration-fd.c @@ -0,0 +1,137 @@ +/* + * QEMU live migration via generic fd + * + * Copyright Red Hat, Inc. 2009 + * + * Authors: + * Chris Lalancette + * + * 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 "monitor.h" +#include "qemu-char.h" +#include "sysemu.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(FdMigrationState *s) +{ + return errno; +} + +static int fd_write(FdMigrationState *s, const void * buf, size_t size) +{ + return write(s->fd, buf, size); +} + +static int fd_close(FdMigrationState *s) +{ + dprintf("fd_close\n"); + if (s->fd != -1) { + close(s->fd); + s->fd = -1; + } + return 0; +} + +MigrationState *fd_start_outgoing_migration(Monitor *mon, + const char *fdname, + int64_t bandwidth_limit, + int detach) +{ + FdMigrationState *s; + + s = qemu_mallocz(sizeof(*s)); + + s->fd = monitor_get_fd(mon, fdname); + if (s->fd == -1) { + dprintf("fd_migration: invalid file descriptor identifier\n"); + goto err_after_alloc; + } + + 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; + 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: + close(s->fd); +err_after_alloc: + qemu_free(s); + return NULL; +} + +static void fd_accept_incoming_migration(void *opaque) +{ + QEMUFile *f = opaque; + int ret; + + 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_stdio_fd(f), NULL, NULL, NULL, NULL); + if (autostart) + vm_start(); + +err: + 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, + (void *)(unsigned long)f); + + return 0; +} diff --git a/migration.c b/migration.c index 34e2bc14c0..c18d595842 100644 --- a/migration.c +++ b/migration.c @@ -45,6 +45,8 @@ void qemu_start_incoming_migration(const char *uri) exec_start_incoming_migration(p); else if (strstart(uri, "unix:", &p)) unix_start_incoming_migration(p); + else if (strstart(uri, "fd:", &p)) + fd_start_incoming_migration(p); #endif else fprintf(stderr, "unknown migration protocol: %s\n", uri); @@ -62,6 +64,8 @@ void do_migrate(Monitor *mon, int detach, const char *uri) s = exec_start_outgoing_migration(p, max_throttle, detach); else if (strstart(uri, "unix:", &p)) s = unix_start_outgoing_migration(p, max_throttle, detach); + else if (strstart(uri, "fd:", &p)) + s = fd_start_outgoing_migration(mon, p, max_throttle, detach); #endif else monitor_printf(mon, "unknown migration protocol: %s\n", uri); diff --git a/migration.h b/migration.h index 0ed1fcb515..96dad38eb5 100644 --- a/migration.h +++ b/migration.h @@ -79,6 +79,13 @@ MigrationState *unix_start_outgoing_migration(const char *path, int64_t bandwidth_limit, int detach); +int fd_start_incoming_migration(const char *path); + +MigrationState *fd_start_outgoing_migration(Monitor *mon, + const char *fdname, + int64_t bandwidth_limit, + int detach); + void migrate_fd_monitor_suspend(FdMigrationState *s); void migrate_fd_error(FdMigrationState *s); diff --git a/savevm.c b/savevm.c index 975e7ab46f..4575653779 100644 --- a/savevm.c +++ b/savevm.c @@ -285,6 +285,34 @@ int qemu_stdio_fd(QEMUFile *f) return fd; } +QEMUFile *qemu_fdopen(int fd, const char *mode) +{ + QEMUFileStdio *s; + + if (mode == NULL || + (mode[0] != 'r' && mode[0] != 'w') || + mode[1] != 'b' || mode[2] != 0) { + fprintf(stderr, "qemu_fdopen: Argument validity check failed\n"); + return NULL; + } + + s = qemu_mallocz(sizeof(QEMUFileStdio)); + s->stdio_file = fdopen(fd, mode); + if (!s->stdio_file) + goto fail; + + if(mode[0] == 'r') { + s->file = qemu_fopen_ops(s, NULL, stdio_get_buffer, stdio_fclose, NULL, NULL); + } else { + s->file = qemu_fopen_ops(s, stdio_put_buffer, NULL, stdio_fclose, NULL, NULL); + } + return s->file; + +fail: + qemu_free(s); + return NULL; +} + QEMUFile *qemu_fopen_socket(int fd) { QEMUFileSocket *s = qemu_mallocz(sizeof(QEMUFileSocket)); -- GitLab