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>
---
migration/file.c | 64 +++++++++++++++++++++++++++++++++++++++++--
migration/file.h | 10 +++++--
migration/migration.c | 2 +-
migration/multifd.c | 14 ++++++++--
migration/options.c | 7 +++++
migration/options.h | 1 +
6 files changed, 90 insertions(+), 8 deletions(-)
diff --git a/migration/file.c b/migration/file.c
index cf5b1bf365..93b9b7bf5d 100644
--- a/migration/file.c
+++ b/migration/file.c
@@ -17,6 +17,12 @@
#define OFFSET_OPTION ",offset="
+static struct FileOutgoingArgs {
+ char *fname;
+ int flags;
+ int mode;
+} outgoing_args;
+
/* Remove the offset option from @filespec and return it in @offsetp. */
static int file_parse_offset(char *filespec, uint64_t *offsetp, Error **errp)
@@ -36,13 +42,62 @@ static int file_parse_offset(char *filespec, uint64_t
*offsetp, Error **errp)
return 0;
}
+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 *filespec,
Error **errp)
{
- g_autofree char *filename = g_strdup(filespec);
g_autoptr(QIOChannelFile) fioc = NULL;
+ g_autofree char *filename = g_strdup(filespec);
uint64_t offset = 0;
QIOChannel *ioc;
+ int flags = O_CREAT | O_TRUNC | O_WRONLY;
+ mode_t mode = 0660;
trace_migration_file_outgoing(filename);
@@ -50,12 +105,15 @@ void file_start_outgoing_migration(MigrationState *s,
const char *filespec,
return;
}
- fioc = qio_channel_file_new_path(filename, O_CREAT | O_WRONLY | O_TRUNC,
- 0600, errp);
+ fioc = qio_channel_file_new_path(filename, flags, mode, errp);
if (!fioc) {
return;
}
+ outgoing_args.fname = g_strdup(filename);
+ outgoing_args.flags = flags;
+ outgoing_args.mode = mode;
+
ioc = QIO_CHANNEL(fioc);
if (offset && qio_channel_io_seek(ioc, offset, SEEK_SET, errp) < 0) {
return;
diff --git a/migration/file.h b/migration/file.h
index 90fa4849e0..10148233c5 100644
--- a/migration/file.h
+++ b/migration/file.h
@@ -7,8 +7,14 @@
#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,
+#include "io/task.h"
+#include "channel.h"
+
+void file_start_incoming_migration(const char *filespec, Error **errp);
+
+void file_start_outgoing_migration(MigrationState *s, const char *filespec,
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 cabb3ad3a5..ba806cea55 100644
--- a/migration/migration.c
+++ b/migration/migration.c
@@ -114,7 +114,7 @@ static bool migration_needs_seekable_channel(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 uri_supports_seeking(const char *uri)
diff --git a/migration/multifd.c b/migration/multifd.c
index b912060b32..75a17ea8ab 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 "migration-stats.h"
@@ -28,6 +29,7 @@
#include "threadinfo.h"
#include "options.h"
#include "qemu/yank.h"
+#include "io/channel-file.h"
#include "io/channel-socket.h"
#include "yank_functions.h"
@@ -512,7 +514,11 @@ 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)
@@ -907,7 +913,11 @@ 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)
diff --git a/migration/options.c b/migration/options.c
index bb7a2bbe06..469d5d4c50 100644
--- a/migration/options.c
+++ b/migration/options.c
@@ -414,6 +414,13 @@ bool migrate_tls(void)
return s->parameters.tls_creds && *s->parameters.tls_creds;
}
+bool migrate_to_file(void)
+{
+ MigrationState *s = migrate_get_current();
+
+ return qemu_file_is_seekable(s->to_dst_file);
+}
+
typedef enum WriteTrackingSupport {
WT_SUPPORT_UNKNOWN = 0,
WT_SUPPORT_ABSENT,
diff --git a/migration/options.h b/migration/options.h
index 4a3e7e36a8..01bba5b928 100644
--- a/migration/options.h
+++ b/migration/options.h
@@ -61,6 +61,7 @@ bool migrate_multifd_packets(void);
bool migrate_postcopy(void);
bool migrate_rdma(void);
bool migrate_tls(void);
+bool migrate_to_file(void);
/* capabilities helpers */
--
2.35.3
