add file descriptor migration (5ac1fad3) · Commits · SUMMER2020 / students / proj-2021291

Makefile

+1 −1

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		@@ -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)

hw/hw.h

+1 −0

Original line number	Diff line number	Diff line
		@@ -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);

migration-fd.c

0 → 100644

+137 −0

Original line number	Diff line number	Diff line
		/*
		* 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.
		*
		*/

		#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;
		}

migration.c

+4 −0

Original line number	Diff line number	Diff line
		@@ -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);

migration.h

+7 −0

Original line number	Diff line number	Diff line
		@@ -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);