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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 10.5.11.13 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="y3Y89HR1TESSwbJiPPRjzy7rfphOR29WG" 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) --y3Y89HR1TESSwbJiPPRjzy7rfphOR29WG Content-Type: multipart/mixed; boundary="7zIYIipchX0rNOmzBMTddVNCJhU8bVaC8" --7zIYIipchX0rNOmzBMTddVNCJhU8bVaC8 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; > + 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) { > + 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) { In case of failure, a negative value is going to be returned, we won=E2=80= =99t go into this conditional block, and local_flags isn=E2=80=99t going to cont= ain BDRV_REQ_COPY_ON_READ. So the idea of CORing in case of failure sounds sound to me, but it doesn=E2=80=99t look like that=E2=80=99s done. > + ret =3D bdrv_is_allocated_above(bdrv_cow_bs(bs->file->bs), I think this should either be bdrv_backing_chain_next() or we must rule out the possibility of bs->file->bs being a filter somewhere. I think I=E2=80=99d prefer the former. > + state->base_overlay, true, off= set, > + n, &n); > + if (ret) { =E2=80=9Cret =3D=3D 1 || ret < 0=E2=80=9D would be more explicit (and in li= ne with the =E2=80=9C!ret || ret < 0=E2=80=9D probably needed above), but correct either way. Max --7zIYIipchX0rNOmzBMTddVNCJhU8bVaC8-- --y3Y89HR1TESSwbJiPPRjzy7rfphOR29WG Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAEBCAAdFiEEkb62CjDbPohX0Rgp9AfbAGHVz0AFAl+G6BoACgkQ9AfbAGHV z0CiHwf+KoxIB1Ldo9PHNVpp0z5CIdSvX/zl3yI/trCoCn/mYf87/EMr3uFYJ8rH vD51FTFTMZ8+Dn7JTZgYNhmH1EbAo27yTdTD4SUba2aa9vVLeWEgRL1wqbPZY/pJ Px0Ju2NkS16E++YKaYNIg20UoZGbSZgzI5d0JYjN6El5uqrDb9f9Mwf/Hk0z7Z9+ GeHrya66KiN2YqsryQ7LQ+ULZDDIJYz6K4wheL54aXaulzReUoIVmjutyoh95ggl fDEyjPAEBYG0h561FSFOy07MtVV7GmFxYPKzDQURAtBXCzndeF1wwFHmQUDZpTUZ 4KAe0+oUqkqa3zhoccFEGQZ3zRn7mw== =cp/7 -----END PGP SIGNATURE----- --y3Y89HR1TESSwbJiPPRjzy7rfphOR29WG--