[SCSI] virtio-scsi: support online resizing of disks

Support the LUN parameter change event.  Currently, the host fires this event
when the capacity of a disk is changed from the virtual machine monitor.
The resize then appears in the kernel log like this:

  sd 0:0:0:0: [sda] 46137344 512-byte logical blocks: (23.6 GB/22.0 GIb)
  sda: detected capacity change from 22548578304 to 23622320128

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
This commit is contained in:
Paolo Bonzini 2012-10-02 17:25:48 +02:00 committed by James Bottomley
parent 9da5f5ac6a
commit 865b58c05b
2 changed files with 32 additions and 1 deletions

View file

@ -279,6 +279,31 @@ static void virtscsi_handle_transport_reset(struct virtio_scsi *vscsi,
}
}
static void virtscsi_handle_param_change(struct virtio_scsi *vscsi,
struct virtio_scsi_event *event)
{
struct scsi_device *sdev;
struct Scsi_Host *shost = virtio_scsi_host(vscsi->vdev);
unsigned int target = event->lun[1];
unsigned int lun = (event->lun[2] << 8) | event->lun[3];
u8 asc = event->reason & 255;
u8 ascq = event->reason >> 8;
sdev = scsi_device_lookup(shost, 0, target, lun);
if (!sdev) {
pr_err("SCSI device %d 0 %d %d not found\n",
shost->host_no, target, lun);
return;
}
/* Handle "Parameters changed", "Mode parameters changed", and
"Capacity data has changed". */
if (asc == 0x2a && (ascq == 0x00 || ascq == 0x01 || ascq == 0x09))
scsi_rescan_device(&sdev->sdev_gendev);
scsi_device_put(sdev);
}
static void virtscsi_handle_event(struct work_struct *work)
{
struct virtio_scsi_event_node *event_node =
@ -297,6 +322,9 @@ static void virtscsi_handle_event(struct work_struct *work)
case VIRTIO_SCSI_T_TRANSPORT_RESET:
virtscsi_handle_transport_reset(vscsi, event);
break;
case VIRTIO_SCSI_T_PARAM_CHANGE:
virtscsi_handle_param_change(vscsi, event);
break;
default:
pr_err("Unsupport virtio scsi event %x\n", event->event);
}
@ -737,7 +765,8 @@ static struct virtio_device_id id_table[] = {
};
static unsigned int features[] = {
VIRTIO_SCSI_F_HOTPLUG
VIRTIO_SCSI_F_HOTPLUG,
VIRTIO_SCSI_F_CHANGE,
};
static struct virtio_driver virtio_scsi_driver = {

View file

@ -72,6 +72,7 @@ struct virtio_scsi_config {
/* Feature Bits */
#define VIRTIO_SCSI_F_INOUT 0
#define VIRTIO_SCSI_F_HOTPLUG 1
#define VIRTIO_SCSI_F_CHANGE 2
/* Response codes */
#define VIRTIO_SCSI_S_OK 0
@ -108,6 +109,7 @@ struct virtio_scsi_config {
#define VIRTIO_SCSI_T_NO_EVENT 0
#define VIRTIO_SCSI_T_TRANSPORT_RESET 1
#define VIRTIO_SCSI_T_ASYNC_NOTIFY 2
#define VIRTIO_SCSI_T_PARAM_CHANGE 3
/* Reasons of transport reset event */
#define VIRTIO_SCSI_EVT_RESET_HARD 0