* Kirti Wankhede (kwankh...@nvidia.com) wrote:
> Sequence during _RESUMING device state:
> While data for this device is available, repeat below steps:
> a. read data_offset from where user application should write data.
> b. write data of data_size to migration region from data_offset.
> c. write data_size which indicates vendor driver that data is written in
> staging buffer.
>
> For user, data is opaque. User should write data in the same order as
> received.
>
> Signed-off-by: Kirti Wankhede <kwankh...@nvidia.com>
> Reviewed-by: Neo Jia <c...@nvidia.com>
> ---
> hw/vfio/migration.c | 179
> +++++++++++++++++++++++++++++++++++++++++++++++++++
> hw/vfio/trace-events | 3 +
> 2 files changed, 182 insertions(+)
>
> diff --git a/hw/vfio/migration.c b/hw/vfio/migration.c
> index ecbeed5182c2..ab295d25620e 100644
> --- a/hw/vfio/migration.c
> +++ b/hw/vfio/migration.c
> @@ -269,6 +269,33 @@ static int vfio_save_device_config_state(QEMUFile *f,
> void *opaque)
> return qemu_file_get_error(f);
> }
>
> +static int vfio_load_device_config_state(QEMUFile *f, void *opaque)
> +{
> + VFIODevice *vbasedev = opaque;
> + uint64_t data;
> +
> + if (vbasedev->ops && vbasedev->ops->vfio_load_config) {
> + int ret;
> +
> + ret = vbasedev->ops->vfio_load_config(vbasedev, f);
> + if (ret) {
> + error_report("%s: Failed to load device config space",
> + vbasedev->name);
> + return ret;
> + }
> + }
> +
> + data = qemu_get_be64(f);
> + if (data != VFIO_MIG_FLAG_END_OF_STATE) {
> + error_report("%s: Failed loading device config space, "
> + "end flag incorrect 0x%"PRIx64, vbasedev->name, data);
> + return -EINVAL;
> + }
> +
> + trace_vfio_load_device_config_state(vbasedev->name);
> + return qemu_file_get_error(f);
> +}
> +
> /* ---------------------------------------------------------------------- */
>
> static int vfio_save_setup(QEMUFile *f, void *opaque)
> @@ -434,12 +461,164 @@ static int vfio_save_complete_precopy(QEMUFile *f,
> void *opaque)
> return ret;
> }
>
> +static int vfio_load_setup(QEMUFile *f, void *opaque)
> +{
> + VFIODevice *vbasedev = opaque;
> + VFIOMigration *migration = vbasedev->migration;
> + int ret = 0;
> +
> + if (migration->region.mmaps) {
> + ret = vfio_region_mmap(&migration->region);
> + if (ret) {
> + error_report("%s: Failed to mmap VFIO migration region %d: %s",
> + vbasedev->name, migration->region.nr,
> + strerror(-ret));
> + return ret;
> + }
> + }
> +
> + ret = vfio_migration_set_state(vbasedev, ~0, VFIO_DEVICE_STATE_RESUMING);
> + if (ret) {
> + error_report("%s: Failed to set state RESUMING", vbasedev->name);
> + }
> + return ret;
> +}
> +
> +static int vfio_load_cleanup(void *opaque)
> +{
> + vfio_save_cleanup(opaque);
> + return 0;
> +}
> +
> +static int vfio_load_state(QEMUFile *f, void *opaque, int version_id)
> +{
> + VFIODevice *vbasedev = opaque;
> + VFIOMigration *migration = vbasedev->migration;
> + int ret = 0;
> + uint64_t data, data_size;
> +
> + data = qemu_get_be64(f);
> + while (data != VFIO_MIG_FLAG_END_OF_STATE) {
> +
> + trace_vfio_load_state(vbasedev->name, data);
> +
> + switch (data) {
> + case VFIO_MIG_FLAG_DEV_CONFIG_STATE:
> + {
> + ret = vfio_load_device_config_state(f, opaque);
> + if (ret) {
> + return ret;
> + }
> + break;
> + }
> + case VFIO_MIG_FLAG_DEV_SETUP_STATE:
> + {
> + uint64_t region_size = qemu_get_be64(f);
> +
> + if (migration->region.size < region_size) {
> + error_report("%s: SETUP STATE: migration region too small, "
> + "0x%"PRIx64 " < 0x%"PRIx64, vbasedev->name,
> + migration->region.size, region_size);
> + return -EINVAL;
> + }
> +
> + data = qemu_get_be64(f);
> + if (data == VFIO_MIG_FLAG_END_OF_STATE) {
Can you explain why you're reading this here rather than letting it drop
through to the read at the end of the loop?
> + return ret;
> + } else {
> + error_report("%s: SETUP STATE: EOS not found 0x%"PRIx64,
> + vbasedev->name, data);
> + return -EINVAL;
> + }
> + break;
> + }
> + case VFIO_MIG_FLAG_DEV_DATA_STATE:
> + {
> + VFIORegion *region = &migration->region;
> + void *buf = NULL;
> + bool buffer_mmaped = false;
> + uint64_t data_offset = 0;
> +
> + data_size = qemu_get_be64(f);
> + if (data_size == 0) {
> + break;
> + }
> +
> + ret = pread(vbasedev->fd, &data_offset, sizeof(data_offset),
> + region->fd_offset +
> + offsetof(struct vfio_device_migration_info,
> + data_offset));
> + if (ret != sizeof(data_offset)) {
> + error_report("%s:Failed to get migration buffer data offset
> %d",
> + vbasedev->name, ret);
> + return -EINVAL;
> + }
> +
> + if (region->mmaps) {
> + buf = find_data_region(region, data_offset, data_size);
> + }
> +
> + buffer_mmaped = (buf != NULL) ? true : false;
> +
> + if (!buffer_mmaped) {
> + buf = g_try_malloc0(data_size);
data_size has been read off the wire at this point; can we sanity check
it?
> + if (!buf) {
> + error_report("%s: Error allocating buffer ", __func__);
> + return -ENOMEM;
> + }
> + }
> +
> + qemu_get_buffer(f, buf, data_size);
> +
> + if (!buffer_mmaped) {
> + ret = pwrite(vbasedev->fd, buf, data_size,
> + region->fd_offset + data_offset);
> + g_free(buf);
> +
> + if (ret != data_size) {
> + error_report("%s: Failed to set migration buffer %d",
> + vbasedev->name, ret);
> + return -EINVAL;
> + }
> + }
> +
> + ret = pwrite(vbasedev->fd, &data_size, sizeof(data_size),
> + region->fd_offset +
> + offsetof(struct vfio_device_migration_info,
> data_size));
> + if (ret != sizeof(data_size)) {
> + error_report("%s: Failed to set migration buffer data size
> %d",
> + vbasedev->name, ret);
> + if (!buffer_mmaped) {
> + g_free(buf);
> + }
> + return -EINVAL;
> + }
> +
> + trace_vfio_load_state_device_data(vbasedev->name, data_offset,
> + data_size);
> + break;
> + }
I'd add here a default: that complains about an unknown tag.
> + }
> +
> + ret = qemu_file_get_error(f);
> + if (ret) {
> + return ret;
> + }
> + data = qemu_get_be64(f);
I'd also check file_get_error again at this point; if you're unlucky you
get junk in 'data' and things get more confusing.
> + }
> +
> + return ret;
> +}
> +
> static SaveVMHandlers savevm_vfio_handlers = {
> .save_setup = vfio_save_setup,
> .save_cleanup = vfio_save_cleanup,
> .save_live_pending = vfio_save_pending,
> .save_live_iterate = vfio_save_iterate,
> .save_live_complete_precopy = vfio_save_complete_precopy,
> + .load_setup = vfio_load_setup,
> + .load_cleanup = vfio_load_cleanup,
> + .load_state = vfio_load_state,
> };
>
> /* ---------------------------------------------------------------------- */
> diff --git a/hw/vfio/trace-events b/hw/vfio/trace-events
> index bdf40ba368c7..ac065b559f4e 100644
> --- a/hw/vfio/trace-events
> +++ b/hw/vfio/trace-events
> @@ -157,3 +157,6 @@ vfio_save_device_config_state(char *name) " (%s)"
> vfio_save_pending(char *name, uint64_t precopy, uint64_t postcopy, uint64_t
> compatible) " (%s) precopy 0x%"PRIx64" postcopy 0x%"PRIx64" compatible
> 0x%"PRIx64
> vfio_save_iterate(char *name, int data_size) " (%s) data_size %d"
> vfio_save_complete_precopy(char *name) " (%s)"
> +vfio_load_device_config_state(char *name) " (%s)"
> +vfio_load_state(char *name, uint64_t data) " (%s) data 0x%"PRIx64
Please use const char*'s in traces.
> +vfio_load_state_device_data(char *name, uint64_t data_offset, uint64_t
> data_size) " (%s) Offset 0x%"PRIx64" size 0x%"PRIx64
> --
> 2.7.0
>
--
Dr. David Alan Gilbert / dgilb...@redhat.com / Manchester, UK
