From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from [140.186.70.92] (port=44719 helo=eggs.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1ObEZn-0002PC-CQ for qemu-devel@nongnu.org; Tue, 20 Jul 2010 11:17:48 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.69) (envelope-from ) id 1ObEZl-00055k-S8 for qemu-devel@nongnu.org; Tue, 20 Jul 2010 11:17:47 -0400 Received: from mx1.redhat.com ([209.132.183.28]:44542) by eggs.gnu.org with esmtp (Exim 4.69) (envelope-from ) id 1ObEZl-000552-LI for qemu-devel@nongnu.org; Tue, 20 Jul 2010 11:17:45 -0400 From: Jes.Sorensen@redhat.com Date: Tue, 20 Jul 2010 17:17:36 +0200 Message-Id: <1279639056-20465-1-git-send-email-Jes.Sorensen@redhat.com> Subject: [Qemu-devel] [PATCH] Disable O_DIRECT for physical CDROM/DVD drives List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org From: Jes Sorensen O_DIRECT (cache=none) requires sector alignment, however the physical sector size of CDROM/DVD drives is 2048, as opposed to most disk devices which use 512. QEMU is hard coding 512 all over the place, so allowing O_DIRECT for CDROM/DVD devices does not work. Signed-off-by: Jes Sorensen --- block/raw-posix.c | 5 +++++ 1 files changed, 5 insertions(+), 0 deletions(-) diff --git a/block/raw-posix.c b/block/raw-posix.c index 291699f..0ea79b6 100644 --- a/block/raw-posix.c +++ b/block/raw-posix.c @@ -1139,6 +1139,11 @@ static int cdrom_open(BlockDriverState *bs, const char *filename, int flags) BDRVRawState *s = bs->opaque; s->type = FTYPE_CD; + if (flags & BDRV_O_NOCACHE) { + fprintf(stderr, "Disabling unsupported O_DIRECT (cache=none) for " + "CDROM/DVD device (%s)\n", filename); + flags &= ~BDRV_O_NOCACHE; + } /* open will not fail even if no CD is inserted, so add O_NONBLOCK */ return raw_open_common(bs, filename, flags, O_NONBLOCK); -- 1.7.1.1