[SCSI] virtio-scsi: fix LUNs greater than 255

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.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>

diff --git a/drivers/scsi/virtio_scsi.c b/drivers/scsi/virtio_scsi.c
index 7554d78564348cee5127a1b05a209d3f9895aea1..a7cf726bc747875fbd2d3515adba623b6dca81fd 100644 (file)
--- 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;