Commit dfb37cf7 authored by Fam Zheng's avatar Fam Zheng Committed by Paolo Bonzini
Browse files

virtio-scsi: Add migration state notifier for dataplane code 



Similar to virtio-blk-dataplane, we stop the iothread while migration
starts and restart it when migration finishes.

Signed-off-by: default avatarFam Zheng <famz@redhat.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent 63c7e542

hw/scsi/virtio-scsi.c

+32 −3
Original line number Diff line number Diff line
@@ -20,6 +20,7 @@ 
#include <block/scsi.h>

#include <hw/virtio/virtio-bus.h>

#include "hw/virtio/virtio-access.h"

#include "migration/migration.h"



static inline int virtio_scsi_get_lun(uint8_t *lun)

{
@@ -357,7 +358,7 @@ static void virtio_scsi_handle_ctrl(VirtIODevice *vdev, VirtQueue *vq) 
    VirtIOSCSI *s = (VirtIOSCSI *)vdev;

    VirtIOSCSIReq *req;



    if (s->ctx) {

    if (s->ctx && !s->dataplane_disabled) {

        virtio_scsi_dataplane_start(s);

        return;

    }
@@ -501,7 +502,7 @@ static void virtio_scsi_handle_cmd(VirtIODevice *vdev, VirtQueue *vq) 
    VirtIOSCSI *s = (VirtIOSCSI *)vdev;

    VirtIOSCSIReq *req;



    if (s->ctx) {

    if (s->ctx && !s->dataplane_disabled) {

        virtio_scsi_dataplane_start(s);

        return;

    }
@@ -651,7 +652,7 @@ static void virtio_scsi_handle_event(VirtIODevice *vdev, VirtQueue *vq) 
{

    VirtIOSCSI *s = VIRTIO_SCSI(vdev);



    if (s->ctx) {

    if (s->ctx && !s->dataplane_disabled) {

        virtio_scsi_dataplane_start(s);

        return;

    }
@@ -742,6 +743,31 @@ void virtio_scsi_common_realize(DeviceState *dev, Error **errp, 
    }

}



/* Disable dataplane thread during live migration since it does not

 * update the dirty memory bitmap yet.

 */

static void virtio_scsi_migration_state_changed(Notifier *notifier, void *data)

{

    VirtIOSCSI *s = container_of(notifier, VirtIOSCSI,

                                 migration_state_notifier);

    MigrationState *mig = data;



    if (migration_in_setup(mig)) {

        if (!s->dataplane_started) {

            return;

        }

        virtio_scsi_dataplane_stop(s);

        s->dataplane_disabled = true;

    } else if (migration_has_finished(mig) ||

               migration_has_failed(mig)) {

        if (s->dataplane_started) {

            return;

        }

        bdrv_drain_all(); /* complete in-flight non-dataplane requests */

        s->dataplane_disabled = false;

    }

}



static void virtio_scsi_device_realize(DeviceState *dev, Error **errp)

{

    VirtIODevice *vdev = VIRTIO_DEVICE(dev);
@@ -770,6 +796,8 @@ static void virtio_scsi_device_realize(DeviceState *dev, Error **errp) 


    register_savevm(dev, "virtio-scsi", virtio_scsi_id++, 1,

                    virtio_scsi_save, virtio_scsi_load, s);

    s->migration_state_notifier.notify = virtio_scsi_migration_state_changed;

    add_migration_state_change_notifier(&s->migration_state_notifier);

}



static void virtio_scsi_instance_init(Object *obj)
@@ -796,6 +824,7 @@ static void virtio_scsi_device_unrealize(DeviceState *dev, Error **errp) 
    VirtIOSCSI *s = VIRTIO_SCSI(dev);



    unregister_savevm(dev, "virtio-scsi", s);

    remove_migration_state_change_notifier(&s->migration_state_notifier);



    virtio_scsi_common_unrealize(dev, errp);

}

include/hw/virtio/virtio-scsi.h

+2 −0
Original line number Diff line number Diff line
@@ -194,6 +194,8 @@ typedef struct VirtIOSCSI { 
    bool dataplane_started;

    bool dataplane_starting;

    bool dataplane_stopping;

    bool dataplane_disabled;

    Notifier migration_state_notifier;

} VirtIOSCSI;



typedef struct VirtIOSCSIReq {