From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:44131) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WLDp4-0000Ot-3n for qemu-devel@nongnu.org; Wed, 05 Mar 2014 10:33:36 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1WLDox-0004oE-M9 for qemu-devel@nongnu.org; Wed, 05 Mar 2014 10:33:30 -0500 Received: from lnantes-156-75-100-125.w80-12.abo.wanadoo.fr ([80.12.84.125]:55710 helo=paradis.irqsave.net) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WLDox-0004oA-GE for qemu-devel@nongnu.org; Wed, 05 Mar 2014 10:33:23 -0500 Date: Wed, 5 Mar 2014 16:33:23 +0100 From: =?iso-8859-1?Q?Beno=EEt?= Canet Message-ID: <20140305153323.GA1709@irqsave.net> References: <1394031649-31915-1-git-send-email-kwolf@redhat.com> <1394031649-31915-2-git-send-email-kwolf@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline In-Reply-To: <1394031649-31915-2-git-send-email-kwolf@redhat.com> Content-Transfer-Encoding: quoted-printable Subject: Re: [Qemu-devel] [PATCH 1/2] iscsi: Use bs->sg for everything else than disks List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Kevin Wolf Cc: pbonzini@redhat.com, pl@kamp.de, qemu-devel@nongnu.org The Wednesday 05 Mar 2014 =E0 16:00:48 (+0100), Kevin Wolf wrote : > The current iscsi block driver code makes the rather arbitrary decision > that TYPE_MEDIUM_CHANGER and TYPE_TAPE devices have bs->sg =3D 1 and al= l > other device types are disks. >=20 > Instead of this, check for TYPE_DISK to expose the disk interface and > make everything else bs->sg =3D 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=3D1067784 for the exac= t > scenario.) >=20 > Signed-off-by: Kevin Wolf > --- > block/iscsi.c | 9 ++++----- > 1 file changed, 4 insertions(+), 5 deletions(-) >=20 > 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, QDi= ct *options, int flags, > bs->total_sectors =3D sector_lun2qemu(iscsilun->num_blocks, iscsil= un); > bs->request_alignment =3D iscsilun->block_size; > =20 > - /* 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 wi= ll 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, otherwi= se qemu > + * will try to read from the device to guess the image format. > */ > - if (iscsilun->type =3D=3D TYPE_MEDIUM_CHANGER || > - iscsilun->type =3D=3D TYPE_TAPE) { > + if (iscsilun->type !=3D TYPE_DISK && iscsilun->type !=3D TYPE_ROM)= { I don't understand you are talking about type TYPE_STORAGE_ARRAY in the c= ommit message but testing against TYPE_ROM and they are not the same. Maybe a comment explaining the role of TYPE_ROM would give a clue to non = scsi savy persons like me. Best regards Beno=EEt > bs->sg =3D 1; > } > =20 > --=20 > 1.8.1.4 >=20 >=20