On 2/9/21 8:29 PM, Mark Cave-Ayland wrote:
> The QOM object representing ESPState is currently embedded within both the
> SYSBUS_ESP and PCI_ESP devices with migration state handled by embedding
> vmstate_esp within each device using VMSTATE_STRUCT.
>
> Since the vmstate_esp fields are embedded directly within the migration
> stream, the incoming vmstate_esp version_id is lost. The only version
> information
> available is that from vmstate_sysbus_esp_scsi and vmstate_esp_pci_scsi, but
> those versions represent their respective devices and not that of the
> underlying
> ESPState.
>
> Resolve this by adding a new version-dependent field in
> vmstate_sysbus_esp_scsi
> and vmstate_esp_pci_scsi which stores the vmstate_esp version_id field within
> ESPState to be used to allow migration from older QEMU versions.
>
> Finally bump the vmstate_esp version to 5 to cover the upcoming ESPState
> changes
> within this patch series.
>
> Signed-off-by: Mark Cave-Ayland <mark.cave-ayl...@ilande.co.uk>
Reviewed-by: Philippe Mathieu-Daudé <f4...@amsat.org>
> ---
> hw/scsi/esp-pci.c | 3 ++-
> hw/scsi/esp.c | 23 +++++++++++++++++++++--
> include/hw/scsi/esp.h | 2 ++
> 3 files changed, 25 insertions(+), 3 deletions(-)
>
> diff --git a/hw/scsi/esp-pci.c b/hw/scsi/esp-pci.c
> index ccf73bb901..8a82404853 100644
> --- a/hw/scsi/esp-pci.c
> +++ b/hw/scsi/esp-pci.c
> @@ -330,11 +330,12 @@ static void esp_pci_hard_reset(DeviceState *dev)
>
> static const VMStateDescription vmstate_esp_pci_scsi = {
> .name = "pciespscsi",
> - .version_id = 1,
> + .version_id = 2,
> .minimum_version_id = 1,
> .fields = (VMStateField[]) {
> VMSTATE_PCI_DEVICE(parent_obj, PCIESPState),
> VMSTATE_BUFFER_UNSAFE(dma_regs, PCIESPState, 0, 8 *
> sizeof(uint32_t)),
> + VMSTATE_UINT8_V(esp.mig_version_id, PCIESPState, 2),
> VMSTATE_STRUCT(esp, PCIESPState, 0, vmstate_esp, ESPState),
> VMSTATE_END_OF_LIST()
> }
> diff --git a/hw/scsi/esp.c b/hw/scsi/esp.c
> index 1635f86622..9427c55d1d 100644
> --- a/hw/scsi/esp.c
> +++ b/hw/scsi/esp.c
> @@ -796,10 +796,28 @@ static const VMStateDescription vmstate_esp_pdma = {
> }
> };
>
> +static int esp_pre_save(void *opaque)
> +{
> + ESPState *s = ESP(opaque);
> +
> + s->mig_version_id = vmstate_esp.version_id;
> + return 0;
> +}
> +
> +static int esp_post_load(void *opaque, int version_id)
> +{
> + ESPState *s = ESP(opaque);
> +
> + s->mig_version_id = vmstate_esp.version_id;
> + return 0;
> +}
> +
> const VMStateDescription vmstate_esp = {
> .name = "esp",
> - .version_id = 4,
> + .version_id = 5,
> .minimum_version_id = 3,
> + .pre_save = esp_pre_save,
> + .post_load = esp_post_load,
> .fields = (VMStateField[]) {
> VMSTATE_BUFFER(rregs, ESPState),
> VMSTATE_BUFFER(wregs, ESPState),
> @@ -996,9 +1014,10 @@ static void sysbus_esp_init(Object *obj)
>
> static const VMStateDescription vmstate_sysbus_esp_scsi = {
> .name = "sysbusespscsi",
> - .version_id = 1,
> + .version_id = 2,
> .minimum_version_id = 1,
> .fields = (VMStateField[]) {
> + VMSTATE_UINT8_V(esp.mig_version_id, SysBusESPState, 2),
> VMSTATE_STRUCT(esp, SysBusESPState, 0, vmstate_esp, ESPState),
> VMSTATE_END_OF_LIST()
> }
> diff --git a/include/hw/scsi/esp.h b/include/hw/scsi/esp.h
> index 11c799d91e..7d92471c5b 100644
> --- a/include/hw/scsi/esp.h
> +++ b/include/hw/scsi/esp.h
> @@ -68,6 +68,8 @@ struct ESPState {
> uint32_t pdma_start;
> uint32_t pdma_cur;
> void (*pdma_cb)(ESPState *s);
> +
> + uint8_t mig_version_id;
> };
>
> #define TYPE_SYSBUS_ESP "sysbus-esp"
>
