---
tools/virsh.pod | 12 +++++++++---
1 file changed, 9 insertions(+), 3 deletions(-)
diff --git a/tools/virsh.pod b/tools/virsh.pod
index cad5b1c..a26c420 100644
--- a/tools/virsh.pod
+++ b/tools/virsh.pod
@@ -1675,9 +1675,15 @@ I<source> is path for the files and devices. I<target>
controls the bus or
device under which the disk is exposed to the guest OS. It indicates the
"logical" device name. I<driver> can be I<file>, I<tap> or
I<phy> for the Xen
hypervisor depending on the kind of access; or I<qemu> for the QEMU emulator.
-I<type> can indicate I<lun>, I<cdrom> or I<floppy> as alternative
to the disk default,
-although this use only replaces the media within the existing virtual cdrom or
-floppy device; consider using B<update-device> for this usage instead.
+Further details to the driver can be passed using I<subdriver>. For Xen
+I<subdriver> can be I<aio>, while for QEMU subdriver should match the format
+of the disk source, such as I<raw> or I<qcow2>. Hypervisor default will be
+used if I<subdriver> is not specified. However, the default may not be
+correct, esp. for QEMU as for security reasons it is configured not to detect
+disk formats. I<type> can indicate I<lun>, I<cdrom> or I<floppy>
as
+alternative to the disk default, although this use only replaces the media
+within the existing virtual cdrom or floppy device; consider using
+B<update-device> for this usage instead.
I<mode> can specify the two specific mode I<readonly> or I<shareable>.
I<--config> indicates the changes will affect the next boot of the domain,
for compatibility purposes, I<--persistent> is alias of I<--config>.
--
1.7.12