virtio-scsi-dataplane: Add op blocker

We need this to protect dataplane thread from race conditions with block
jobs until the latter is made dataplane-safe.

Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Fam Zheng 2014-10-19 12:47:42 +08:00 committed by Paolo Bonzini
parent e40830afa1
commit 3e2b2a9c49
3 changed files with 22 additions and 2 deletions

View file

@ -155,6 +155,8 @@ void virtio_scsi_dataplane_start(VirtIOSCSI *s)
s->dataplane_starting = true;
assert(!s->blocker);
error_setg(&s->blocker, "block device is in use by data plane");
/* Set up guest notifier (irq) */
rc = k->set_guest_notifiers(qbus->parent, vs->conf.num_queues + 2, true);
if (rc != 0) {
@ -195,6 +197,8 @@ void virtio_scsi_dataplane_stop(VirtIOSCSI *s)
if (!s->dataplane_started || s->dataplane_stopping) {
return;
}
error_free(s->blocker);
s->blocker = NULL;
s->dataplane_stopping = true;
assert(s->ctx == iothread_get_aio_context(vs->conf.iothread));

View file

@ -742,9 +742,18 @@ static void virtio_scsi_hotplug(HotplugHandler *hotplug_dev, DeviceState *dev,
Error **errp)
{
VirtIODevice *vdev = VIRTIO_DEVICE(hotplug_dev);
VirtIOSCSI *s = VIRTIO_SCSI(vdev);
SCSIDevice *sd = SCSI_DEVICE(dev);
if (s->ctx && !s->dataplane_disabled) {
if (blk_op_is_blocked(sd->conf.blk, BLOCK_OP_TYPE_DATAPLANE, errp)) {
return;
}
blk_op_block_all(sd->conf.blk, s->blocker);
}
if ((vdev->guest_features >> VIRTIO_SCSI_F_HOTPLUG) & 1) {
virtio_scsi_push_event(VIRTIO_SCSI(hotplug_dev), SCSI_DEVICE(dev),
virtio_scsi_push_event(s, sd,
VIRTIO_SCSI_T_TRANSPORT_RESET,
VIRTIO_SCSI_EVT_RESET_RESCAN);
}
@ -754,12 +763,18 @@ static void virtio_scsi_hotunplug(HotplugHandler *hotplug_dev, DeviceState *dev,
Error **errp)
{
VirtIODevice *vdev = VIRTIO_DEVICE(hotplug_dev);
VirtIOSCSI *s = VIRTIO_SCSI(vdev);
SCSIDevice *sd = SCSI_DEVICE(dev);
if ((vdev->guest_features >> VIRTIO_SCSI_F_HOTPLUG) & 1) {
virtio_scsi_push_event(VIRTIO_SCSI(hotplug_dev), SCSI_DEVICE(dev),
virtio_scsi_push_event(s, sd,
VIRTIO_SCSI_T_TRANSPORT_RESET,
VIRTIO_SCSI_EVT_RESET_REMOVED);
}
if (s->ctx) {
blk_op_unblock_all(sd->conf.blk, s->blocker);
}
qdev_simple_device_unplug_cb(hotplug_dev, dev, errp);
}

View file

@ -195,6 +195,7 @@ typedef struct VirtIOSCSI {
bool dataplane_starting;
bool dataplane_stopping;
bool dataplane_disabled;
Error *blocker;
Notifier migration_state_notifier;
} VirtIOSCSI;