[PATCH 0/2] virtio-scsi fixes for 3.6

[PATCH 0/2] virtio-scsi fixes for 3.6

[Paolo Bonzini]

James,

patch 1 fixes scanning of LUNs whose number is greater than 255.  QEMU
passes a max_lun of 16383 (because it uses SAM numbering) but in Linux
it must become 32768 (because LUNs above 255 are "relocated" to 16640).
Patch 2 is a resubmission of the patch for online resizing of virtio-scsi
LUNs, which needs to be rebased.

LUNs above 255 now work for all of scanning, hotplug, hotunplug and
resize.

Thanks,

Paolo

Paolo Bonzini (2):
  virtio-scsi: fix LUNs greater than 255
  virtio-scsi: support online resizing of disks

 drivers/scsi/virtio_scsi.c  |   37 +++++++++++++++++++++++++++++++++++--
 include/linux/virtio_scsi.h |    2 ++
 2 files changed, 37 insertions(+), 2 deletions(-)

[PATCH 1/2] virtio-scsi: fix LUNs greater than 255

[Paolo Bonzini]

virtio-scsi needs to report LUNs greater than 256 using the "flat"
format.  Because the Linux SCSI layer just maps the SCSI LUN to
an u32, without any parsing, these end up in the range from 16640
to 32767.  Fix max_lun to account for the possibility that logical
unit numbers are encoded with the "flat" format.

Cc: <stable@vger.kernel.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 drivers/scsi/virtio_scsi.c |    6 +++++-
 1 files changed, 5 insertions(+), 1 deletions(-)

diff --git a/drivers/scsi/virtio_scsi.c b/drivers/scsi/virtio_scsi.c
index c7030fb..8b6b927 100644
--- a/drivers/scsi/virtio_scsi.c
+++ b/drivers/scsi/virtio_scsi.c
@@ -677,7 +677,11 @@ static int __devinit virtscsi_probe(struct virtio_device *vdev)
 	cmd_per_lun = virtscsi_config_get(vdev, cmd_per_lun) ?: 1;
 	shost->cmd_per_lun = min_t(u32, cmd_per_lun, shost->can_queue);
 	shost->max_sectors = virtscsi_config_get(vdev, max_sectors) ?: 0xFFFF;
-	shost->max_lun = virtscsi_config_get(vdev, max_lun) + 1;
+
+	/* LUNs > 256 are reported with format 1, so they go in the range
+	 * 16640-32767.
+	 */
+	shost->max_lun = virtscsi_config_get(vdev, max_lun) + 1 + 0x4000;
 	shost->max_id = num_targets;
 	shost->max_channel = 0;
 	shost->max_cmd_len = VIRTIO_SCSI_CDB_SIZE;
-- 
1.7.1

[PATCH 2/2] virtio-scsi: support online resizing of disks

[Paolo Bonzini]

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>
---
 drivers/scsi/virtio_scsi.c  |   31 ++++++++++++++++++++++++++++++-
 include/linux/virtio_scsi.h |    2 ++
 2 files changed, 32 insertions(+), 1 deletions(-)

diff --git a/drivers/scsi/virtio_scsi.c b/drivers/scsi/virtio_scsi.c
index 8b6b927..c1a5e60 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
-- 
1.7.1

Re: [PATCH 0/2] virtio-scsi fixes for 3.6

[Paolo Bonzini]

Il 26/07/2012 15:28, Paolo Bonzini ha scritto:
> James,
> 
> patch 1 fixes scanning of LUNs whose number is greater than 255.  QEMU
> passes a max_lun of 16383 (because it uses SAM numbering) but in Linux
> it must become 32768 (because LUNs above 255 are "relocated" to 16640).
> Patch 2 is a resubmission of the patch for online resizing of virtio-scsi
> LUNs, which needs to be rebased.
> 
> LUNs above 255 now work for all of scanning, hotplug, hotunplug and
> resize.
> 
> Thanks,
> 
> Paolo
> 
> Paolo Bonzini (2):
>   virtio-scsi: fix LUNs greater than 255
>   virtio-scsi: support online resizing of disks
> 
>  drivers/scsi/virtio_scsi.c  |   37 +++++++++++++++++++++++++++++++++++--
>  include/linux/virtio_scsi.h |    2 ++
>  2 files changed, 37 insertions(+), 2 deletions(-)
> 

Ping, are these patches going into 3.7?

Paolo

Re: [PATCH 0/2] virtio-scsi fixes for 3.6

[Paolo Bonzini]

Il 02/10/2012 10:18, James Bottomley ha scritto:
> On Mon, 2012-10-01 at 15:11 +0200, Paolo Bonzini wrote:
>> Il 26/07/2012 15:28, Paolo Bonzini ha scritto:
>>> James,
>>>
>>> patch 1 fixes scanning of LUNs whose number is greater than 255.  QEMU
>>> passes a max_lun of 16383 (because it uses SAM numbering) but in Linux
>>> it must become 32768 (because LUNs above 255 are "relocated" to 16640).
>>> Patch 2 is a resubmission of the patch for online resizing of virtio-scsi
>>> LUNs, which needs to be rebased.
>>>
>>> LUNs above 255 now work for all of scanning, hotplug, hotunplug and
>>> resize.
>>>
>>> Thanks,
>>>
>>> Paolo
>>>
>>> Paolo Bonzini (2):
>>>   virtio-scsi: fix LUNs greater than 255
>>>   virtio-scsi: support online resizing of disks
>>>
>>>  drivers/scsi/virtio_scsi.c  |   37 +++++++++++++++++++++++++++++++++++--
>>>  include/linux/virtio_scsi.h |    2 ++
>>>  2 files changed, 37 insertions(+), 2 deletions(-)
>>>
>>
>> Ping, are these patches going into 3.7?
> 
> They're 3.7 candidates yes (enhancements certainly aren't 3.6).
> I seem to have become lost with the virtio-scsi updates since what I have
> marked for inclusion is a patch series that's a partial intersection
> with this.  I'll flush my queue for virto-scsi, please resend all the
> missing patches you want in 3.7.

Ok, will do so soon and tag the appropriate ones for stable.

Paolo