Am 05.03.2014 16:00, schrieb Kevin Wolf: > 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: Kevin Wolf <kw...@redhat.com> > --- > block/iscsi.c | 9 ++++----- > 1 file changed, 4 insertions(+), 5 deletions(-) > > diff --git a/block/iscsi.c b/block/iscsi.c > index 0a15f53..b490e98 100644 > --- a/block/iscsi.c > +++ b/block/iscsi.c > @@ -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; > } > We have ioctl support in the iscsi block driver only for Linux. Is this a problem?
Peter
