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Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.11.0 MIME-Version: 1.0 In-Reply-To: <1602524605-481160-8-git-send-email-andrey.shinkevich@virtuozzo.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=mreitz@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="DItM25f0dWH9klXINxTRDwQoqD9sZqsip" Received-SPF: pass client-ip=216.205.24.124; envelope-from=mreitz@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/10/14 01:12:43 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] [fuzzy] X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, NICE_REPLY_A=-0.001, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: kwolf@redhat.com, fam@euphon.net, vsementsov@virtuozzo.com, libvir-list@redhat.com, qemu-devel@nongnu.org, armbru@redhat.com, stefanha@redhat.com, den@openvz.org, jsnow@redhat.com Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" This is an OpenPGP/MIME signed message (RFC 4880 and 3156) --DItM25f0dWH9klXINxTRDwQoqD9sZqsip Content-Type: multipart/mixed; boundary="eI9An60utN0S3013nH0mOCXmFyBwxesOG" --eI9An60utN0S3013nH0mOCXmFyBwxesOG Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: quoted-printable On 12.10.20 19:43, Andrey Shinkevich wrote: > Add the new member supported_read_flags to BlockDriverState structure. > It will control the BDRV_REQ_PREFETCH flag set for copy-on-read > operations. >=20 > Signed-off-by: Andrey Shinkevich > --- > include/block/block_int.h | 4 ++++ > 1 file changed, 4 insertions(+) Not sure what the problem with passing BDRV_REQ_PREFETCH to drivers that aren=E2=80=99t the COR filter are would be, but: Reviewed-by: Max Reitz (I mean, outside of the context of COR the flag is undefined, so it can be anything, but intuitively I=E2=80=99d assume it means =E2=80=9Cno need t= o read the data to memory=E2=80=9D then, too. So if a driver doesn=E2=80=99t support = it, nothing bad should happen. Hm. Well, unless the driver passes the flag on (unsuspectingly) and a metadata-bearing child doesn=E2=80=99t return any da= ta that the drviver needs. Yeah, better to explicitly disallow the flag for all unsupporting drivers then.) --eI9An60utN0S3013nH0mOCXmFyBwxesOG-- --DItM25f0dWH9klXINxTRDwQoqD9sZqsip Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAEBCAAdFiEEkb62CjDbPohX0Rgp9AfbAGHVz0AFAl+G74QACgkQ9AfbAGHV z0DRsAf/XFvYf/8tgctiFBo6ZDtmLHyRznxrlc5WtEvAsVFcMUnzB20u81bmo+YN bVqenkz2C/mxja3d791eFefmcPrgn6arntuRpTWQW05qSXVuXrfW2e3xFJBOlRdQ vT/qPnjnlJ1Uu5E84/f10ORBydqIDK5iqwd0lUm1rAVP/c8K2snCIqF668E71oWk oa6C39UV5FdojPUMAEqZl3/mGVvYEcoPAl1HJr13sZMtnFflnP2aHWKFQsDpsczh U9UTGmBbBMTMgQX9sgbljSJ4VLsd64a8WwFFZxiNUdMTxHUHx+cnMymseNsNO1UB U6KuKUvrzN/Z0SfuFFSHLGRAuw16hQ== =Yhms -----END PGP SIGNATURE----- --DItM25f0dWH9klXINxTRDwQoqD9sZqsip--