Extend the migration URI to support file:<filename>. This can be used for
any migration scenario that does not require a reverse path. It can be used
as an alternative to 'exec:cat > file' in minimized containers that do not
contain /bin/sh, and it is easier to use than the fd:<fdname> URI. It can
be used in HMP commands, and as a qemu command-line parameter.
Signed-off-by: Steve Sistare <steven.sist...@oracle.com>
---
migration/file.c | 62 ++++++++++++++++++++++++++++++++++++++++++++++++++
migration/file.h | 14 ++++++++++++
migration/meson.build | 1 +
migration/migration.c | 5 ++++
migration/trace-events | 4 ++++
qemu-options.hx | 6 ++++-
6 files changed, 91 insertions(+), 1 deletion(-)
create mode 100644 migration/file.c
create mode 100644 migration/file.h
diff --git a/migration/file.c b/migration/file.c
new file mode 100644
index 0000000..8e35827
--- /dev/null
+++ b/migration/file.c
@@ -0,0 +1,62 @@
+/*
+ * Copyright (c) 2021-2023 Oracle and/or its affiliates.
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2.
+ * See the COPYING file in the top-level directory.
+ */
+
+#include "qemu/osdep.h"
+#include "channel.h"
+#include "file.h"
+#include "migration.h"
+#include "io/channel-file.h"
+#include "io/channel-util.h"
+#include "trace.h"
+
+void file_start_outgoing_migration(MigrationState *s, const char *filename,
+ Error **errp)
+{
+ g_autoptr(QIOChannelFile) fioc = NULL;
+ QIOChannel *ioc;
+
+ trace_migration_file_outgoing(filename);
+
+ fioc = qio_channel_file_new_path(filename, O_CREAT | O_WRONLY | O_TRUNC,
+ 0600, errp);
+ if (!fioc) {
+ return;
+ }
+
+ ioc = QIO_CHANNEL(fioc);
+ qio_channel_set_name(ioc, "migration-file-outgoing");
+ migration_channel_connect(s, ioc, NULL, NULL);
+}
+
+static gboolean file_accept_incoming_migration(QIOChannel *ioc,
+ GIOCondition condition,
+ gpointer opaque)
+{
+ migration_channel_process_incoming(ioc);
+ object_unref(OBJECT(ioc));
+ return G_SOURCE_REMOVE;
+}
+
+void file_start_incoming_migration(const char *filename, Error **errp)
+{
+ QIOChannelFile *fioc = NULL;
+ QIOChannel *ioc;
+
+ trace_migration_file_incoming(filename);
+
+ fioc = qio_channel_file_new_path(filename, O_RDONLY, 0, errp);
+ if (!fioc) {
+ return;
+ }
+
+ ioc = QIO_CHANNEL(fioc);
+ qio_channel_set_name(QIO_CHANNEL(ioc), "migration-file-incoming");
+ qio_channel_add_watch_full(ioc, G_IO_IN,
+ file_accept_incoming_migration,
+ NULL, NULL,
+ g_main_context_get_thread_default());
+}
diff --git a/migration/file.h b/migration/file.h
new file mode 100644
index 0000000..841b94a
--- /dev/null
+++ b/migration/file.h
@@ -0,0 +1,14 @@
+/*
+ * Copyright (c) 2021-2023 Oracle and/or its affiliates.
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2.
+ * See the COPYING file in the top-level directory.
+ */
+
+#ifndef QEMU_MIGRATION_FILE_H
+#define QEMU_MIGRATION_FILE_H
+void file_start_incoming_migration(const char *filename, Error **errp);
+
+void file_start_outgoing_migration(MigrationState *s, const char *filename,
+ Error **errp);
+#endif
diff --git a/migration/meson.build b/migration/meson.build
index 8ba6e42..3af817e 100644
--- a/migration/meson.build
+++ b/migration/meson.build
@@ -16,6 +16,7 @@ softmmu_ss.add(files(
'dirtyrate.c',
'exec.c',
'fd.c',
+ 'file.c',
'global_state.c',
'migration-hmp-cmds.c',
'migration.c',
diff --git a/migration/migration.c b/migration/migration.c
index dc05c6f..cfbde86 100644
--- a/migration/migration.c
+++ b/migration/migration.c
@@ -20,6 +20,7 @@
#include "migration/blocker.h"
#include "exec.h"
#include "fd.h"
+#include "file.h"
#include "socket.h"
#include "sysemu/runstate.h"
#include "sysemu/sysemu.h"
@@ -442,6 +443,8 @@ static void qemu_start_incoming_migration(const char *uri,
Error **errp)
exec_start_incoming_migration(p, errp);
} else if (strstart(uri, "fd:", &p)) {
fd_start_incoming_migration(p, errp);
+ } else if (strstart(uri, "file:", &p)) {
+ file_start_incoming_migration(p, errp);
} else {
error_setg(errp, "unknown migration protocol: %s", uri);
}
@@ -1662,6 +1665,8 @@ void qmp_migrate(const char *uri, bool has_blk, bool blk,
exec_start_outgoing_migration(s, p, &local_err);
} else if (strstart(uri, "fd:", &p)) {
fd_start_outgoing_migration(s, p, &local_err);
+ } else if (strstart(uri, "file:", &p)) {
+ file_start_outgoing_migration(s, p, &local_err);
} else {
if (!(has_resume && resume)) {
yank_unregister_instance(MIGRATION_YANK_INSTANCE);
diff --git a/migration/trace-events b/migration/trace-events
index cdaef7a..c8c1771 100644
--- a/migration/trace-events
+++ b/migration/trace-events
@@ -307,6 +307,10 @@ migration_exec_incoming(const char *cmd) "cmd=%s"
migration_fd_outgoing(int fd) "fd=%d"
migration_fd_incoming(int fd) "fd=%d"
+# file.c
+migration_file_outgoing(const char *filename) "filename=%s"
+migration_file_incoming(const char *filename) "filename=%s"
+
# socket.c
migration_socket_incoming_accepted(void) ""
migration_socket_outgoing_connected(const char *hostname) "hostname=%s"
diff --git a/qemu-options.hx b/qemu-options.hx
index b37eb96..b93449d 100644
--- a/qemu-options.hx
+++ b/qemu-options.hx
@@ -4610,6 +4610,7 @@ DEF("incoming", HAS_ARG, QEMU_OPTION_incoming, \
" prepare for incoming migration, listen on\n" \
" specified protocol and socket address\n" \
"-incoming fd:fd\n" \
+ "-incoming file:filename\n" \
"-incoming exec:cmdline\n" \
" accept incoming migration on given file descriptor\n" \
" or from given external command\n" \
@@ -4626,7 +4627,10 @@ SRST
Prepare for incoming migration, listen on a given unix socket.
``-incoming fd:fd``
- Accept incoming migration from a given filedescriptor.
+ Accept incoming migration from a given file descriptor.
+
+``-incoming file:filename``
+ Accept incoming migration from a given file.
``-incoming exec:cmdline``
Accept incoming migration as an output from specified external
--
1.8.3.1
