Commit f47c3f5a authored by Kevin Wolf's avatar Kevin Wolf
Browse files

iscsi: Use bs->sg for everything else than disks 

The current iscsi block driver code makes the rather arbitrary decision
that TYPE_MEDIUM_CHANGER and TYPE_TAPE devices have bs->sg = 1 and all
other device types are disks.

Instead of this, check for TYPE_DISK to expose the disk interface and
make everything else bs->sg = 1. In particular, this includes devices
with TYPE_STORAGE_ARRAY, which is what LUN 0 of an iscsi target is.
(See https://bugzilla.redhat.com/show_bug.cgi?id=1067784

 for the exact
scenario.)

Signed-off-by: default avatarKevin Wolf <kwolf@redhat.com>
Reviewed-by: default avatarBenoit Canet <benoit@irqsave.net>
Acked-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent 2fa4c042

block/iscsi.c

+4 −5
Original line number Diff line number Diff line
@@ -1231,12 +1231,11 @@ static int iscsi_open(BlockDriverState *bs, QDict *options, int flags, 
    bs->total_sectors = sector_lun2qemu(iscsilun->num_blocks, iscsilun);

    bs->request_alignment = iscsilun->block_size;



    /* Medium changer or tape. We dont have any emulation for this so this must

     * be sg ioctl compatible. We force it to be sg, otherwise qemu will try

     * to read from the device to guess the image format.

    /* We don't have any emulation for devices other than disks and CD-ROMs, so

     * this must be sg ioctl compatible. We force it to be sg, otherwise qemu

     * will try to read from the device to guess the image format.

     */

    if (iscsilun->type == TYPE_MEDIUM_CHANGER ||

        iscsilun->type == TYPE_TAPE) {

    if (iscsilun->type != TYPE_DISK && iscsilun->type != TYPE_ROM) {

        bs->sg = 1;

    }