From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:52490) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XUB7j-0007DA-6I for qemu-devel@nongnu.org; Wed, 17 Sep 2014 05:02:09 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1XUB7d-0005Cv-Ri for qemu-devel@nongnu.org; Wed, 17 Sep 2014 05:02:03 -0400 Received: from mail-wi0-x22c.google.com ([2a00:1450:400c:c05::22c]:40987) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XUB7d-0005C3-Ku for qemu-devel@nongnu.org; Wed, 17 Sep 2014 05:01:57 -0400 Received: by mail-wi0-f172.google.com with SMTP id e4so774561wiv.17 for ; Wed, 17 Sep 2014 02:01:53 -0700 (PDT) Date: Wed, 17 Sep 2014 10:01:50 +0100 From: Stefan Hajnoczi Message-ID: <20140917090150.GA10699@stefanha-thinkpad.redhat.com> References: <3B064E40-49ED-487A-A4ED-EA57B2ED05D3@163.com> <20140916144642.GE10303@stefanha-thinkpad.redhat.com> <4483414C-AE50-4371-944D-AED207A61E2C@163.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="UugvWAfsgieZRqgk" Content-Disposition: inline In-Reply-To: <4483414C-AE50-4371-944D-AED207A61E2C@163.com> Subject: Re: [Qemu-devel] Data classification in Qemu List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Wu Libin Cc: Paolo Bonzini , qemu-devel@nongnu.org --UugvWAfsgieZRqgk Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Tue, Sep 16, 2014 at 11:03:04PM +0800, Wu Libin wrote: > Yeah, i know dm-cache, it=E2=80=99s in the layer of block. >=20 > Maybe my description is not clear enough.Just because i see a patch, it w= ill set flags which can classify IO size in bio->bi_flags, and in the funct= ion sd_prep_fn, it will set the SCSI command depends on the bio->bi_flags, = like: > SCpnt->cmnd[6] =3D DSS_BIO_CLASS(SCpnt->request->bio); >=20 > And i see the data classification function will be enabled when the devic= e model is =E2=80=9CQEMU=E2=80=9D, so i guess the QEMU must can recognise t= he SCSI command. That=E2=80=99s why i will search the data classification a= bout the QEMU. >=20 > It=E2=80=99s true QEMU not care about the filesystem, but we have flags, = right, -:). After a web search I guess you are are talking about this paper: http://sigops.org/sosp/sosp11/current/2011-Cascais/printable/05-mesnier.pdf The code isn't upstream and I've never heard of it. I think you should get in touch with the authors instead. Stefan --UugvWAfsgieZRqgk Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQEcBAEBAgAGBQJUGU3+AAoJEJykq7OBq3PIVXcH/0kqY8g+OH714aZMcSwltPQL mtvmzju993IuBr8taNmumsEPqDBjBeIj54P3OKAGlMVRqIyAQMOo4pZJwSoktwL1 Oc1kP5JnKFlCu7sCqpa++L6uZE1MSkIpAVP+ZLqaWVQKI3YqAcwBGpVqbM0g9VDy XMhCi9oIsyk4xfyOPfmF+9Jw3G1NB1EptYJ4lrbSb/96cX059A88ABMvrK6n4oQz 7zLoLEdnCSZy1pAco11BUY+NasnvvJ6UGH3r0iQRXcgbyVSPMUzbfZ2y0DOmMZRu 6Y16Ye4/oxIsQ20ax7G4PM9MFER3QbQhXUFpSE5pjjjY5hD7ufWLJ5oCX2vonKQ= =+saP -----END PGP SIGNATURE----- --UugvWAfsgieZRqgk--