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Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.11.0 MIME-Version: 1.0 In-Reply-To: <1602524605-481160-7-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="hvQX7PGeHNTEbHgR2QynqEl8aNRtW9Ugq" Received-SPF: pass client-ip=63.128.21.124; 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 03:37:33 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_H5=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) --hvQX7PGeHNTEbHgR2QynqEl8aNRtW9Ugq Content-Type: multipart/mixed; boundary="SoScWs07FhQp7vphvyNlnfUIzTKINYtAW" --SoScWs07FhQp7vphvyNlnfUIzTKINYtAW 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: > Modify the comment for the flag BDRV_REQ_PREFETCH as we are going to > use it alone and pass it to the COR-filter driver for further > processing. >=20 > Signed-off-by: Andrey Shinkevich > --- > include/block/block.h | 7 ++++--- > 1 file changed, 4 insertions(+), 3 deletions(-) >=20 > diff --git a/include/block/block.h b/include/block/block.h > index 981ab5b..2b7efd1 100644 > --- a/include/block/block.h > +++ b/include/block/block.h > @@ -71,9 +71,10 @@ typedef enum { > BDRV_REQ_NO_FALLBACK =3D 0x100, > =20 > /* > - * BDRV_REQ_PREFETCH may be used only together with BDRV_REQ_COPY_ON= _READ > - * on read request and means that caller doesn't really need data to= be > - * written to qiov parameter which may be NULL. > + * BDRV_REQ_PREFETCH may be used together with the BDRV_REQ_COPY_ON_= READ > + * flag or when the COR-filter applied to read operations and means = that There=E2=80=99s some word missing here, but I=E2=80=99m not sure what it is= ... At least an =E2=80=9Cis=E2=80=9D before =E2=80=9Capplied=E2=80=9D. Perhaps somethin= g like =E2=80=9Dor when a COR filter is involved (in read operations)=E2=80=9D would be better. > + * caller doesn't really need data to be written to qiov parameter w= hich And this =E2=80=9Cwritten to=E2=80=9D confused me for a second, because we= =E2=80=99re reading into qiov. Technically, that means writing into the buffer, but, you know. Could we rewrite the whole thing, perhaps? Something like =E2=80=9CBDRV_REQ_PREFETCH makes sense only in the context of copy-on-read (i.e., together with the BDRV_REQ_COPY_ON_READ flag or when there is a COR filter), in which case it signals that the COR operation need not read the data into memory (qiov), but only ensure it is copied to the top layer (i.e., that COR is done).=E2=80=9D I don=E2=80=99t know. Max > + * may be NULL. > */ > BDRV_REQ_PREFETCH =3D 0x200, > /* Mask of valid flags */ >=20 --SoScWs07FhQp7vphvyNlnfUIzTKINYtAW-- --hvQX7PGeHNTEbHgR2QynqEl8aNRtW9Ugq Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAEBCAAdFiEEkb62CjDbPohX0Rgp9AfbAGHVz0AFAl+G7YUACgkQ9AfbAGHV z0BXmwgAiBWP7j0xsnO5pLw1EKomh0zpGS3Wvm99kVMAHPw+KzgAXj1PACe1HEWp ng4uFxl2Lxd6rf4+1wyQFsqJONdWQdRo20rpf15d2DDFnnTEbxOiqfDCgsqJ6uTD +g1LKv2KXIvCqkh9y3FxrcqzAUeb1y3Qt56HpI3CJzMrUNlYGPAC0mr+KBnBpqEd szDIm28jRPI4oZQ/+webBM1wPyKBQ6EF9Mimr8JyjmRXaxKeO6oIABBBogt817D6 GKb05WAJIrRJSiAyEfdHbNUgMM8EsMtbv1C3xFfOahdlJ2EMmzlzHgGNTVefFsjr U0I6DC3tNHJOq1yVg4nusLISqeEjnQ== =MoGN -----END PGP SIGNATURE----- --hvQX7PGeHNTEbHgR2QynqEl8aNRtW9Ugq--