Allow multifd to open file-backed channels. This will be used when
enabling the fixed-ram migration stream format which expects a
seekable transport.
The QIOChannel read and write methods will use the preadv/pwritev
versions which don't update the file offset at each call so we can
reuse the fd without re-opening for every channel.
Note that this is just setup code and multifd cannot yet make use of
the file channels.
Signed-off-by: Fabiano Rosas <faro...@suse.de>
---
include/io/channel-file.h | 1 +
migration/file.c | 63 +++++++++++++++++++++++++++++++++++++--
migration/file.h | 6 +++-
migration/migration.c | 11 ++++++-
migration/migration.h | 1 +
migration/multifd.c | 14 +++++++--
6 files changed, 89 insertions(+), 7 deletions(-)
diff --git a/include/io/channel-file.h b/include/io/channel-file.h
index 50e8eb1138..85b6c34a72 100644
--- a/include/io/channel-file.h
+++ b/include/io/channel-file.h
@@ -22,6 +22,7 @@
#define QIO_CHANNEL_FILE_H
#include "io/channel.h"
+#include "io/task.h"
#include "qom/object.h"
#define TYPE_QIO_CHANNEL_FILE "qio-channel-file"
diff --git a/migration/file.c b/migration/file.c
index ab4e12926c..f674cd1bdb 100644
--- a/migration/file.c
+++ b/migration/file.c
@@ -1,20 +1,77 @@
#include "qemu/osdep.h"
-#include "channel.h"
#include "io/channel-file.h"
#include "file.h"
#include "qemu/error-report.h"
+static struct FileOutgoingArgs {
+ char *fname;
+ int flags;
+ int mode;
+} outgoing_args;
+
+static void qio_channel_file_connect_worker(QIOTask *task, gpointer opaque)
+{
+ /* noop */
+}
+
+static void file_migration_cancel(Error *errp)
+{
+ MigrationState *s;
+
+ s = migrate_get_current();
+
+ migrate_set_state(&s->state, MIGRATION_STATUS_SETUP,
+ MIGRATION_STATUS_FAILED);
+ migration_cancel(errp);
+}
+
+int file_send_channel_destroy(QIOChannel *ioc)
+{
+ if (ioc) {
+ qio_channel_close(ioc, NULL);
+ object_unref(OBJECT(ioc));
+ }
+ g_free(outgoing_args.fname);
+ outgoing_args.fname = NULL;
+
+ return 0;
+}
+
+void file_send_channel_create(QIOTaskFunc f, void *data)
+{
+ QIOChannelFile *ioc;
+ QIOTask *task;
+ Error *errp = NULL;
+
+ ioc = qio_channel_file_new_path(outgoing_args.fname,
+ outgoing_args.flags,
+ outgoing_args.mode, &errp);
+ if (!ioc) {
+ file_migration_cancel(errp);
+ return;
+ }
+
+ task = qio_task_new(OBJECT(ioc), f, (gpointer)data, NULL);
+ qio_task_run_in_thread(task, qio_channel_file_connect_worker,
+ (gpointer)data, NULL, NULL);
+}
void file_start_outgoing_migration(MigrationState *s, const char *fname, Error
**errp)
{
QIOChannelFile *ioc;
+ int flags = O_CREAT | O_TRUNC | O_WRONLY;
+ mode_t mode = 0660;
- ioc = qio_channel_file_new_path(fname, O_CREAT | O_TRUNC | O_WRONLY, 0660,
errp);
+ ioc = qio_channel_file_new_path(fname, flags, mode, errp);
if (!ioc) {
- error_report("Error creating a channel");
+ error_report("Error creating migration outgoing channel");
return;
}
+ outgoing_args.fname = g_strdup(fname);
+ outgoing_args.flags = flags;
+ outgoing_args.mode = mode;
+
qio_channel_set_name(QIO_CHANNEL(ioc), "migration-file-outgoing");
migration_channel_connect(s, QIO_CHANNEL(ioc), NULL, NULL);
object_unref(OBJECT(ioc));
diff --git a/migration/file.h b/migration/file.h
index cdbd291322..5e27ca6afd 100644
--- a/migration/file.h
+++ b/migration/file.h
@@ -1,10 +1,14 @@
#ifndef QEMU_MIGRATION_FILE_H
#define QEMU_MIGRATION_FILE_H
+#include "io/task.h"
+#include "channel.h"
+
void file_start_outgoing_migration(MigrationState *s,
const char *filename,
Error **errp);
void file_start_incoming_migration(const char *fname, Error **errp);
+void file_send_channel_create(QIOTaskFunc f, void *data);
+int file_send_channel_destroy(QIOChannel *ioc);
#endif
-
diff --git a/migration/migration.c b/migration/migration.c
index c647fbffa6..6594c2f404 100644
--- a/migration/migration.c
+++ b/migration/migration.c
@@ -194,7 +194,7 @@ static bool migration_needs_multiple_sockets(void)
static bool uri_supports_multi_channels(const char *uri)
{
return strstart(uri, "tcp:", NULL) || strstart(uri, "unix:", NULL) ||
- strstart(uri, "vsock:", NULL);
+ strstart(uri, "vsock:", NULL) || strstart(uri, "file:", NULL);
}
static bool
@@ -2740,6 +2740,15 @@ bool migrate_pause_before_switchover(void)
MIGRATION_CAPABILITY_PAUSE_BEFORE_SWITCHOVER];
}
+bool migrate_to_file(void)
+{
+ MigrationState *s;
+
+ s = migrate_get_current();
+
+ return qemu_file_is_seekable(s->to_dst_file);
+}
+
int migrate_multifd_channels(void)
{
MigrationState *s;
diff --git a/migration/migration.h b/migration/migration.h
index d7a014ce57..8459201958 100644
--- a/migration/migration.h
+++ b/migration/migration.h
@@ -425,6 +425,7 @@ bool migrate_multifd_use_packets(void);
bool migrate_auto_converge(void);
bool migrate_use_multifd(void);
bool migrate_pause_before_switchover(void);
+bool migrate_to_file(void);
int migrate_multifd_channels(void);
MultiFDCompression migrate_multifd_compression(void);
int migrate_multifd_zlib_level(void);
diff --git a/migration/multifd.c b/migration/multifd.c
index 9f6b2787ed..50bd9b32eb 100644
--- a/migration/multifd.c
+++ b/migration/multifd.c
@@ -17,6 +17,7 @@
#include "exec/ramblock.h"
#include "qemu/error-report.h"
#include "qapi/error.h"
+#include "file.h"
#include "ram.h"
#include "migration.h"
#include "socket.h"
@@ -27,6 +28,7 @@
#include "threadinfo.h"
#include "qemu/yank.h"
+#include "io/channel-file.h"
#include "io/channel-socket.h"
#include "yank_functions.h"
@@ -514,7 +516,11 @@ static void multifd_send_terminate_threads(Error *err)
static int multifd_send_channel_destroy(QIOChannel *send)
{
- return socket_send_channel_destroy(send);
+ if (migrate_to_file()) {
+ return file_send_channel_destroy(send);
+ } else {
+ return socket_send_channel_destroy(send);
+ }
}
void multifd_save_cleanup(void)
@@ -919,7 +925,11 @@ static void multifd_new_send_channel_async(QIOTask *task,
gpointer opaque)
static void multifd_new_send_channel_create(gpointer opaque)
{
- socket_send_channel_create(multifd_new_send_channel_async, opaque);
+ if (migrate_to_file()) {
+ file_send_channel_create(multifd_new_send_channel_async, opaque);
+ } else {
+ socket_send_channel_create(multifd_new_send_channel_async, opaque);
+ }
}
int multifd_save_setup(Error **errp)
--
2.35.3
