blkfront: do not create a PV cdrom device if xen_hvm_guest
It is not possible to unplug emulated cdrom devices, and PV cdroms don't
handle media insert, eject and stream, so we are better off disabling PV
cdroms when running as a Xen HVM guest.
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
diff --git a/drivers/block/xen-blkfront.c b/drivers/block/xen-blkfront.c
index 6eb2989..f63ac3d 100644
--- a/drivers/block/xen-blkfront.c
+++ b/drivers/block/xen-blkfront.c
@@ -738,21 +738,34 @@
}
}
- /* no unplug has been done: do not hook devices != xen vbds */
- if (xen_hvm_domain() && (xen_platform_pci_unplug & XEN_UNPLUG_IGNORE)) {
- int major;
+ if (xen_hvm_domain()) {
+ char *type;
+ int len;
+ /* no unplug has been done: do not hook devices != xen vbds */
+ if (xen_platform_pci_unplug & XEN_UNPLUG_IGNORE) {
+ int major;
- if (!VDEV_IS_EXTENDED(vdevice))
- major = BLKIF_MAJOR(vdevice);
- else
- major = XENVBD_MAJOR;
+ if (!VDEV_IS_EXTENDED(vdevice))
+ major = BLKIF_MAJOR(vdevice);
+ else
+ major = XENVBD_MAJOR;
- if (major != XENVBD_MAJOR) {
- printk(KERN_INFO
- "%s: HVM does not support vbd %d as xen block device\n",
- __FUNCTION__, vdevice);
+ if (major != XENVBD_MAJOR) {
+ printk(KERN_INFO
+ "%s: HVM does not support vbd %d as xen block device\n",
+ __FUNCTION__, vdevice);
+ return -ENODEV;
+ }
+ }
+ /* do not create a PV cdrom device if we are an HVM guest */
+ type = xenbus_read(XBT_NIL, dev->nodename, "device-type", &len);
+ if (IS_ERR(type))
+ return -ENODEV;
+ if (strncmp(type, "cdrom", 5) == 0) {
+ kfree(type);
return -ENODEV;
}
+ kfree(type);
}
info = kzalloc(sizeof(*info), GFP_KERNEL);
if (!info) {