qemu-e2k/migration/file.c
Fabiano Rosas d117ed0699 migration/multifd: Allow receiving pages without packets
Currently multifd does not need to have knowledge of pages on the
receiving side because all the information needed is within the
packets that come in the stream.

We're about to add support to mapped-ram migration, which cannot use
packets because it expects the ramblock section in the migration file
to contain only the guest pages data.

Add a data structure to transfer pages between the ram migration code
and the multifd receiving threads.

We don't want to reuse MultiFDPages_t for two reasons:

a) multifd threads don't really need to know about the data they're
   receiving.

b) the receiving side has to be stopped to load the pages, which means
   we can experiment with larger granularities than page size when
   transferring data.

Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Fabiano Rosas <farosas@suse.de>
Link: https://lore.kernel.org/r/20240229153017.2221-16-farosas@suse.de
Signed-off-by: Peter Xu <peterx@redhat.com>
2024-03-01 15:42:04 +08:00

97 lines
2.8 KiB
C

/*
* Copyright (c) 2021-2023 Oracle and/or its affiliates.
*
* This work is licensed under the terms of the GNU GPL, version 2 or later.
* See the COPYING file in the top-level directory.
*/
#include "qemu/osdep.h"
#include "exec/ramblock.h"
#include "qemu/cutils.h"
#include "qapi/error.h"
#include "channel.h"
#include "file.h"
#include "migration.h"
#include "io/channel-file.h"
#include "io/channel-util.h"
#include "trace.h"
#define OFFSET_OPTION ",offset="
/* Remove the offset option from @filespec and return it in @offsetp. */
int file_parse_offset(char *filespec, uint64_t *offsetp, Error **errp)
{
char *option = strstr(filespec, OFFSET_OPTION);
int ret;
if (option) {
*option = 0;
option += sizeof(OFFSET_OPTION) - 1;
ret = qemu_strtosz(option, NULL, offsetp);
if (ret) {
error_setg_errno(errp, -ret, "file URI has bad offset %s", option);
return -1;
}
}
return 0;
}
void file_start_outgoing_migration(MigrationState *s,
FileMigrationArgs *file_args, Error **errp)
{
g_autoptr(QIOChannelFile) fioc = NULL;
g_autofree char *filename = g_strdup(file_args->filename);
uint64_t offset = file_args->offset;
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);
if (offset && qio_channel_io_seek(ioc, offset, SEEK_SET, errp) < 0) {
return;
}
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(FileMigrationArgs *file_args, Error **errp)
{
g_autofree char *filename = g_strdup(file_args->filename);
QIOChannelFile *fioc = NULL;
uint64_t offset = file_args->offset;
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);
if (offset && qio_channel_io_seek(ioc, offset, SEEK_SET, errp) < 0) {
return;
}
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());
}