tree 966a2bbdc0d9083ee704961e4ee9212e8c1f3fbe
parent 983924532f61091fd90d1f2fafa4aa938c414dbb
author Ronnie Sahlberg <ronniesahlberg@gmail.com> 1338008201 +1000
committer Paolo Bonzini <pbonzini@redhat.com> 1341217121 +0200

ISCSI: force use of sg for SMC and SSC devices

If the device we open is a SMC or SSC device, then force the use of sg. We
dont have any medium changer or tape emulation so only passthrough via
real sg or scsi-generic via iscsi would work anyway.

Forcing sg also makes qemu skip trying to read from the device to guess
the image format by reading from the device (find_image_format()).
SMC devices do not implement READ6/10/12/16 so it is not possible to
read from them (SSC have different CDBs).

With this patch I can successfully manage a SMC device wiht iscsi in
passthrough mode.

Signed-off-by: Ronnie Sahlberg <ronniesahlberg@gmail.com>
[Added TYPE_TAPE handling - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>