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Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.11.0 MIME-Version: 1.0 In-Reply-To: <1602524605-481160-6-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="ORo1HqaNwTkiG9vEV181JwuMUCss4W3nw" 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) --ORo1HqaNwTkiG9vEV181JwuMUCss4W3nw Content-Type: multipart/mixed; boundary="pdXmV3AcNWsgp0iyP3ZDdZILHaK3QjKmY" --pdXmV3AcNWsgp0iyP3ZDdZILHaK3QjKmY 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: > Limit COR operations by the base node in the backing chain when the > overlay base node name is given. It will be useful for a block stream > job when the COR-filter is applied. The overlay base node is passed as > the base itself may change due to concurrent commit jobs on the same > backing chain. >=20 > Signed-off-by: Andrey Shinkevich > --- > block/copy-on-read.c | 39 +++++++++++++++++++++++++++++++++++++-- > 1 file changed, 37 insertions(+), 2 deletions(-) >=20 > diff --git a/block/copy-on-read.c b/block/copy-on-read.c > index c578b1b..dfbd6ad 100644 > --- a/block/copy-on-read.c > +++ b/block/copy-on-read.c > @@ -122,8 +122,43 @@ static int coroutine_fn cor_co_preadv_part(BlockDriv= erState *bs, > size_t qiov_offset, > int flags) > { > - return bdrv_co_preadv_part(bs->file, offset, bytes, qiov, qiov_offse= t, > - flags | BDRV_REQ_COPY_ON_READ); > + int64_t n =3D 0; > + int64_t size =3D offset + bytes; Just when I hit send I noticed that =E2=80=9Cend=E2=80=9D would be a more f= itting name for this variable. > + int local_flags; > + int ret; > + BDRVStateCOR *state =3D bs->opaque; > + > + if (!state->base_overlay) { > + return bdrv_co_preadv_part(bs->file, offset, bytes, qiov, qiov_o= ffset, > + flags | BDRV_REQ_COPY_ON_READ); > + } > + > + while (offset < size) { (because I got a bit confused looking at this) (Though dropping @size (or @end) and just checking when @bytes becomes 0 should work, too.) > + local_flags =3D flags; > + > + /* In case of failure, try to copy-on-read anyway */ > + ret =3D bdrv_is_allocated(bs->file->bs, offset, bytes, &n); > + if (!ret) { > + ret =3D bdrv_is_allocated_above(bdrv_cow_bs(bs->file->bs), > + state->base_overlay, true, off= set, > + n, &n); > + if (ret) { > + local_flags |=3D BDRV_REQ_COPY_ON_READ; > + } > + } Furthermore, I just noticed =E2=80=93 can the is_allocated functions not re= turn 0 in @n, when @offset is a the EOF? Is that something to look out for? (I=E2=80=99m not sure.) Max > + > + ret =3D bdrv_co_preadv_part(bs->file, offset, n, qiov, qiov_offs= et, > + local_flags); > + if (ret < 0) { > + return ret; > + } > + > + offset +=3D n; > + qiov_offset +=3D n; > + bytes -=3D n; > + } > + > + return 0; > } > =20 > =20 >=20 --pdXmV3AcNWsgp0iyP3ZDdZILHaK3QjKmY-- --ORo1HqaNwTkiG9vEV181JwuMUCss4W3nw Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAEBCAAdFiEEkb62CjDbPohX0Rgp9AfbAGHVz0AFAl+G6KAACgkQ9AfbAGHV z0AQlAgAoY6VwV881pfGXy4iekBVJliHszTA1wptdNZ3m/INoJzcIf7Urk46fZqH hW5+TiZwKc3p1+6VFU9blxkngetd3gV2/yhvbmQItBHgGEI7MCSnnCmkJkW4mxcS Rrst6Jj1M4SxohnXRwLu/5eLiAvvo+YV+OYtQa19Jl8XWsLlt/+/HibW2yORqQdr UENsEXIHnk3AoASt++jKnHQ+oW57+0GUCnxnFQvq8hjPK6Y8VfPdKIqgsOcpGc2M 3Et35Ao+BaPOkxO6IwzcbHtjmQWPHs6AgSM+oU73R1/xcPlkx6TPvjAiQeXd1vRq 0xDkdN+YBrjBwqewZBxTscXPOFXWCw== =KhJm -----END PGP SIGNATURE----- --ORo1HqaNwTkiG9vEV181JwuMUCss4W3nw--