From 865b58c05b841964f48f574c2027311bd04db8a1 Mon Sep 17 00:00:00 2001 From: Paolo Bonzini Date: Tue, 2 Oct 2012 17:25:48 +0200 Subject: [PATCH] [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 Signed-off-by: James Bottomley --- drivers/scsi/virtio_scsi.c | 31 ++++++++++++++++++++++++++++++- include/linux/virtio_scsi.h | 2 ++ 2 files changed, 32 insertions(+), 1 deletion(-) diff --git a/drivers/scsi/virtio_scsi.c b/drivers/scsi/virtio_scsi.c index a7cf726..595af1a 100644 --- a/drivers/scsi/virtio_scsi.c +++ b/drivers/scsi/virtio_scsi.c @@ -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 = { diff --git a/include/linux/virtio_scsi.h b/include/linux/virtio_scsi.h index dc8d305..d6b4440 100644 --- a/include/linux/virtio_scsi.h +++ b/include/linux/virtio_scsi.h @@ -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 -- 2.7.4