On 3/4/25 23:03, Maciej S. Szmigiero wrote:
> From: "Maciej S. Szmigiero" <maciej.szmigiero@oracle.com>
>
> Load device config received via multifd using the existing machinery
> behind vfio_load_device_config_state().
>
> Also, make sure to process the relevant main migration channel flags.
>
> Signed-off-by: Maciej S. Szmigiero <maciej.szmigiero@oracle.com>
Reviewed-by: CĂ©dric Le Goater <clg@redhat.com>
Thanks,
C.
> ---
> hw/vfio/migration-multifd.c | 49 +++++++++++++++++++++++++++++++++--
> hw/vfio/migration.c | 9 ++++++-
> include/hw/vfio/vfio-common.h | 2 ++
> 3 files changed, 57 insertions(+), 3 deletions(-)
>
> diff --git a/hw/vfio/migration-multifd.c b/hw/vfio/migration-multifd.c
> index 2eef27604e4f..1d81233c755f 100644
> --- a/hw/vfio/migration-multifd.c
> +++ b/hw/vfio/migration-multifd.c
> @@ -17,6 +17,7 @@
> #include "qemu/lockable.h"
> #include "qemu/main-loop.h"
> #include "qemu/thread.h"
> +#include "io/channel-buffer.h"
> #include "migration/qemu-file.h"
> #include "migration-multifd.h"
> #include "trace.h"
> @@ -193,8 +194,52 @@ bool vfio_multifd_load_state_buffer(void *opaque, char *data, size_t data_size,
> static bool vfio_load_bufs_thread_load_config(VFIODevice *vbasedev,
> Error **errp)
> {
> - error_setg(errp, "not yet there");
> - return false;
> + VFIOMigration *migration = vbasedev->migration;
> + VFIOMultifd *multifd = migration->multifd;
> + VFIOStateBuffer *lb;
> + g_autoptr(QIOChannelBuffer) bioc = NULL;
> + g_autoptr(QEMUFile) f_out = NULL, f_in = NULL;
> + uint64_t mig_header;
> + int ret;
> +
> + assert(multifd->load_buf_idx == multifd->load_buf_idx_last);
> + lb = vfio_state_buffers_at(&multifd->load_bufs, multifd->load_buf_idx);
> + assert(lb->is_present);
> +
> + bioc = qio_channel_buffer_new(lb->len);
> + qio_channel_set_name(QIO_CHANNEL(bioc), "vfio-device-config-load");
> +
> + f_out = qemu_file_new_output(QIO_CHANNEL(bioc));
> + qemu_put_buffer(f_out, (uint8_t *)lb->data, lb->len);
> +
> + ret = qemu_fflush(f_out);
> + if (ret) {
> + error_setg(errp, "%s: load config state flush failed: %d",
> + vbasedev->name, ret);
> + return false;
> + }
> +
> + qio_channel_io_seek(QIO_CHANNEL(bioc), 0, 0, NULL);
> + f_in = qemu_file_new_input(QIO_CHANNEL(bioc));
> +
> + mig_header = qemu_get_be64(f_in);
> + if (mig_header != VFIO_MIG_FLAG_DEV_CONFIG_STATE) {
> + error_setg(errp, "%s: expected FLAG_DEV_CONFIG_STATE but got %" PRIx64,
> + vbasedev->name, mig_header);
> + return false;
> + }
> +
> + bql_lock();
> + ret = vfio_load_device_config_state(f_in, vbasedev);
> + bql_unlock();
> +
> + if (ret < 0) {
> + error_setg(errp, "%s: vfio_load_device_config_state() failed: %d",
> + vbasedev->name, ret);
> + return false;
> + }
> +
> + return true;
> }
>
> static VFIOStateBuffer *vfio_load_state_buffer_get(VFIOMultifd *multifd)
> diff --git a/hw/vfio/migration.c b/hw/vfio/migration.c
> index 0096344f74f9..f325a619c3ed 100644
> --- a/hw/vfio/migration.c
> +++ b/hw/vfio/migration.c
> @@ -264,7 +264,7 @@ static int vfio_save_device_config_state(QEMUFile *f, void *opaque,
> return ret;
> }
>
> -static int vfio_load_device_config_state(QEMUFile *f, void *opaque)
> +int vfio_load_device_config_state(QEMUFile *f, void *opaque)
> {
> VFIODevice *vbasedev = opaque;
> uint64_t data;
> @@ -723,6 +723,13 @@ static int vfio_load_state(QEMUFile *f, void *opaque, int version_id)
> switch (data) {
> case VFIO_MIG_FLAG_DEV_CONFIG_STATE:
> {
> + if (vfio_multifd_transfer_enabled(vbasedev)) {
> + error_report("%s: got DEV_CONFIG_STATE in main migration "
> + "channel but doing multifd transfer",
> + vbasedev->name);
> + return -EINVAL;
> + }
> +
> return vfio_load_device_config_state(f, opaque);
> }
> case VFIO_MIG_FLAG_DEV_SETUP_STATE:
> diff --git a/include/hw/vfio/vfio-common.h b/include/hw/vfio/vfio-common.h
> index 40382390692d..9d72ac1eae8a 100644
> --- a/include/hw/vfio/vfio-common.h
> +++ b/include/hw/vfio/vfio-common.h
> @@ -298,6 +298,8 @@ void vfio_mig_add_bytes_transferred(unsigned long val);
> bool vfio_device_state_is_running(VFIODevice *vbasedev);
> bool vfio_device_state_is_precopy(VFIODevice *vbasedev);
>
> +int vfio_load_device_config_state(QEMUFile *f, void *opaque);
> +
> #ifdef CONFIG_LINUX
> int vfio_get_region_info(VFIODevice *vbasedev, int index,
> struct vfio_region_info **info);
>