From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([209.51.188.92]:59363) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gvjWr-0000Ah-Vy for qemu-devel@nongnu.org; Mon, 18 Feb 2019 09:04:20 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1gvjWq-0004Un-23 for qemu-devel@nongnu.org; Mon, 18 Feb 2019 09:04:17 -0500 From: Stefano Garzarella Date: Mon, 18 Feb 2019 15:02:54 +0100 Message-Id: <20190218140301.197408-4-sgarzare@redhat.com> In-Reply-To: <20190218140301.197408-1-sgarzare@redhat.com> References: <20190218140301.197408-1-sgarzare@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Subject: [Qemu-devel] [PATCH v5 03/10] virtio-blk: add "discard" and "write-zeroes" properties List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: "Michael S. Tsirkin" , "Dr . David Alan Gilbert" , Kevin Wolf , Eduardo Habkost , Laurent Vivier , Marcel Apfelbaum , Paolo Bonzini , Stefan Hajnoczi , Jason Wang , qemu-block@nongnu.org, Max Reitz , Thomas Huth In order to avoid migration issues, we enable DISCARD and WRITE_ZEROES features only for machine type >=3D 4.0 As discussed with Michael S. Tsirkin and Stefan Hajnoczi on the list [1], DISCARD operation should not have security implications (eg. page cache attacks), so we can enable it by default. [1] https://lists.gnu.org/archive/html/qemu-devel/2019-02/msg00504.html Suggested-by: Dr. David Alan Gilbert Reviewed-by: Michael S. Tsirkin Reviewed-by: Stefan Hajnoczi Signed-off-by: Stefano Garzarella --- hw/block/virtio-blk.c | 4 ++++ hw/core/machine.c | 2 ++ 2 files changed, 6 insertions(+) diff --git a/hw/block/virtio-blk.c b/hw/block/virtio-blk.c index 7813237756..f7cd322811 100644 --- a/hw/block/virtio-blk.c +++ b/hw/block/virtio-blk.c @@ -1027,6 +1027,10 @@ static Property virtio_blk_properties[] =3D { DEFINE_PROP_UINT16("queue-size", VirtIOBlock, conf.queue_size, 128), DEFINE_PROP_LINK("iothread", VirtIOBlock, conf.iothread, TYPE_IOTHRE= AD, IOThread *), + DEFINE_PROP_BIT64("discard", VirtIOBlock, host_features, + VIRTIO_BLK_F_DISCARD, true), + DEFINE_PROP_BIT64("write-zeroes", VirtIOBlock, host_features, + VIRTIO_BLK_F_WRITE_ZEROES, true), DEFINE_PROP_END_OF_LIST(), }; =20 diff --git a/hw/core/machine.c b/hw/core/machine.c index 077fbd182a..766ca5899d 100644 --- a/hw/core/machine.c +++ b/hw/core/machine.c @@ -33,6 +33,8 @@ GlobalProperty hw_compat_3_1[] =3D { { "usb-kbd", "serial", "42" }, { "usb-mouse", "serial", "42" }, { "usb-kbd", "serial", "42" }, + { "virtio-blk-device", "discard", "false" }, + { "virtio-blk-device", "write-zeroes", "false" }, }; const size_t hw_compat_3_1_len =3D G_N_ELEMENTS(hw_compat_3_1); =20 --=20 2.20.1