From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from [140.186.70.92] (port=59875 helo=eggs.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1PzUxY-00047t-25 for qemu-devel@nongnu.org; Tue, 15 Mar 2011 10:10:53 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1PzUxW-0002PS-Rg for qemu-devel@nongnu.org; Tue, 15 Mar 2011 10:10:51 -0400 Received: from verein.lst.de ([213.95.11.211]:42960 helo=newverein.lst.de) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1PzUxW-0002PD-LP for qemu-devel@nongnu.org; Tue, 15 Mar 2011 10:10:50 -0400 Date: Tue, 15 Mar 2011 15:10:49 +0100 From: Christoph Hellwig Message-ID: <20110315141049.GA30627@lst.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Subject: [Qemu-devel] [PATCH, RFC 0/4] allow guest control of the volatile write cache List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: kwolf@redhat.com, stefanha@gmail.com, "prerna@linux.vnet.ibm.com Anthony Liguori" This series adds support for the guest to control the volatile write cache setting on disks exported by qemu for ide and virtio. For ide it just wires up the existing SETFEATURES calls, and for virtio it adds a new writeable config space field. SCSI is not supported at this point, as the convoluted callback mess in the SCSI stack doesn't allow commands except for plain WRITEs to read data from guest memory. The backend is based on the code that Prerna posted a while ago, and not Stefan's /proc based variant. I'm open to either one, but the problem with the /proc based one is that it's Linux-specific.