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.
Contrary to the socket migration, the file migration doesn't need an
asynchronous channel creation process, so expose
multifd_channel_connect() and call it directly.
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 | 40 ++++++++++++++++++++++++++++++++++++++--
migration/file.h | 5 +++++
migration/multifd.c | 27 ++++++++++++++++++++++-----
migration/multifd.h | 2 ++
4 files changed, 67 insertions(+), 7 deletions(-)
diff --git a/migration/file.c b/migration/file.c
index 22d052a71f..ac9f6ae40a 100644
--- a/migration/file.c
+++ b/migration/file.c
@@ -12,12 +12,17 @@
#include "channel.h"
#include "file.h"
#include "migration.h"
+#include "multifd.h"
#include "io/channel-file.h"
#include "io/channel-util.h"
#include "trace.h"
#define OFFSET_OPTION ",offset="
+static struct FileOutgoingArgs {
+ char *fname;
+} outgoing_args;
+
/* Remove the offset option from @filespec and return it in @offsetp. */
int file_parse_offset(char *filespec, uint64_t *offsetp, Error **errp)
@@ -37,6 +42,34 @@ int file_parse_offset(char *filespec, uint64_t *offsetp,
Error **errp)
return 0;
}
+int file_send_channel_destroy(QIOChannel *ioc)
+{
+ if (ioc) {
+ qio_channel_close(ioc, NULL);
+ }
+ g_free(outgoing_args.fname);
+ outgoing_args.fname = NULL;
+
+ return 0;
+}
+
+bool file_send_channel_create(gpointer opaque, Error **errp)
+{
+ QIOChannelFile *ioc;
+ int flags = O_WRONLY;
+
+ ioc = qio_channel_file_new_path(outgoing_args.fname, flags, 0, errp);
+ if (!ioc) {
+ return false;
+ }
+
+ if (!multifd_channel_connect(opaque, QIO_CHANNEL(ioc), errp)) {
+ return false;
+ }
+
+ return true;
+}
+
void file_start_outgoing_migration(MigrationState *s,
FileMigrationArgs *file_args, Error **errp)
{
@@ -44,15 +77,18 @@ void file_start_outgoing_migration(MigrationState *s,
g_autofree char *filename = g_strdup(file_args->filename);
uint64_t offset = file_args->offset;
QIOChannel *ioc;
+ int flags = O_CREAT | O_TRUNC | O_WRONLY;
+ mode_t mode = 0660;
trace_migration_file_outgoing(filename);
- 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);
+
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 37d6a08bfc..90794b494b 100644
--- a/migration/file.h
+++ b/migration/file.h
@@ -9,10 +9,15 @@
#define QEMU_MIGRATION_FILE_H
#include "qapi/qapi-types-migration.h"
+#include "io/task.h"
+#include "channel.h"
void file_start_incoming_migration(FileMigrationArgs *file_args, Error **errp);
void file_start_outgoing_migration(MigrationState *s,
FileMigrationArgs *file_args, Error **errp);
int file_parse_offset(char *filespec, uint64_t *offsetp, Error **errp);
+
+bool file_send_channel_create(gpointer opaque, Error **errp);
+int file_send_channel_destroy(QIOChannel *ioc);
#endif
diff --git a/migration/multifd.c b/migration/multifd.c
index 45a0c7aaa8..507b497d52 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"
@@ -680,6 +682,9 @@ static void multifd_send_terminate_threads(void)
static int multifd_send_channel_destroy(QIOChannel *send)
{
+ if (!multifd_use_packets()) {
+ return file_send_channel_destroy(send);
+ }
return socket_send_channel_destroy(send);
}
@@ -959,9 +964,8 @@ static bool multifd_tls_channel_connect(MultiFDSendParams
*p,
return true;
}
-static bool multifd_channel_connect(MultiFDSendParams *p,
- QIOChannel *ioc,
- Error **errp)
+bool multifd_channel_connect(MultiFDSendParams *p, QIOChannel *ioc,
+ Error **errp)
{
qio_channel_set_delay(ioc, false);
@@ -1031,9 +1035,14 @@ out:
error_free(local_err);
}
-static void multifd_new_send_channel_create(gpointer opaque)
+static bool multifd_new_send_channel_create(gpointer opaque, Error **errp)
{
+ if (!multifd_use_packets()) {
+ return file_send_channel_create(opaque, errp);
+ }
+
socket_send_channel_create(multifd_new_send_channel_async, opaque);
+ return true;
}
bool multifd_send_setup(void)
@@ -1082,7 +1091,15 @@ bool multifd_send_setup(void)
p->page_size = qemu_target_page_size();
p->page_count = page_count;
p->write_flags = 0;
- multifd_new_send_channel_create(p);
+
+ if (!multifd_new_send_channel_create(p, &local_err)) {
+ /*
+ * File channel creation is synchronous, we don't need the
+ * semaphore below, it's safe to return now.
+ */
+ assert(migrate_fixed_ram());
+ return -1;
+ }
}
if (use_packets) {
diff --git a/migration/multifd.h b/migration/multifd.h
index 19188815a3..135f6ed098 100644
--- a/migration/multifd.h
+++ b/migration/multifd.h
@@ -228,5 +228,7 @@ static inline void
multifd_send_prepare_header(MultiFDSendParams *p)
p->iovs_num++;
}
+bool multifd_channel_connect(MultiFDSendParams *p, QIOChannel *ioc,
+ Error **errp);
#endif
--
2.35.3
