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Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: <20200818142851.GD6865@linux.fritz.box> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=mreitz@redhat.com X-Mimecast-Spam-Score: 0.0 X-Mimecast-Originator: redhat.com Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="azRFbMc4OzYqnx7Mx8JQ7g90JXmBjF7RC" 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 = 2020/08/19 10:07:28 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] [fuzzy] X-Spam_score_int: -40 X-Spam_score: -4.1 X-Spam_bar: ---- X-Spam_report: (-4.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-1, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H5=-1, RCVD_IN_MSPIKE_WL=-0.01, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=unavailable 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: Vladimir Sementsov-Ogievskiy , qemu-devel@nongnu.org, qemu-block@nongnu.org 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) --azRFbMc4OzYqnx7Mx8JQ7g90JXmBjF7RC Content-Type: multipart/mixed; boundary="PR8o9sQbEqo0bwdQ3qSECuflBURFpAP5r" --PR8o9sQbEqo0bwdQ3qSECuflBURFpAP5r Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: quoted-printable On 18.08.20 16:28, Kevin Wolf wrote: > Am 25.06.2020 um 17:21 hat Max Reitz geschrieben: >> Because of the (not so recent anymore) changes that make the stream job >> independent of the base node and instead track the node above it, we >> have to split that "bottom" node into two cases: The bottom COW node, >> and the node directly above the base node (which may be an R/W filter >> or the bottom COW node). >> >> Signed-off-by: Max Reitz >> --- >> qapi/block-core.json | 4 +++ >> block/stream.c | 63 ++++++++++++++++++++++++++++++++------------ >> blockdev.c | 4 ++- >> 3 files changed, 53 insertions(+), 18 deletions(-) >> >> diff --git a/qapi/block-core.json b/qapi/block-core.json >> index b20332e592..df87855429 100644 >> --- a/qapi/block-core.json >> +++ b/qapi/block-core.json >> @@ -2486,6 +2486,10 @@ >> # On successful completion the image file is updated to drop the backin= g file >> # and the BLOCK_JOB_COMPLETED event is emitted. >> # >> +# In case @device is a filter node, block-stream modifies the first non= -filter >> +# overlay node below it to point to base's backing node (or NULL if @ba= se was >> +# not specified) instead of modifying @device itself. >=20 > Not to @base's backing node, but to @base itself (or actually, to > above_base's backing node, which is initially @base, but may have > changed when the job is completed). Oh, yes. (I thought I had noticed that already at some point and fixed it locally... But apparently not.) > Should we also document what using a filter node for @base means? Hm. What does it mean? I think the more interesting case is what it means if above_base is a filter, right? Maybe we can put in somewhere in the =E2=80=9CIf a base file is specified t= hen sectors are not copied from that base file and its backing chain.=E2=80=9D = But the more I think about it, the less I know what we could add to it. What happens if there are filters above @base is that their data isn=E2=80= =99t copied, because that=E2=80=99s exactly the data in @base. Max --PR8o9sQbEqo0bwdQ3qSECuflBURFpAP5r-- --azRFbMc4OzYqnx7Mx8JQ7g90JXmBjF7RC Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAEBCAAdFiEEkb62CjDbPohX0Rgp9AfbAGHVz0AFAl89O4EACgkQ9AfbAGHV z0Aojgf+PwDpbApo/7g3XZDl52ggNbItoIKEhp/2HYynQl9crIZk3W3QLifjkI9x ITdrFkxb+A1nR3wzG42avnz4eDG0lptrciDG9tpj3FV4X+avSwkYbW6sv+jGmOzO XPy8A17LUFmiiRwhTO37mpjkw9UnhGvOSnAMtZ0yrFJIpzB7zqfdOpslhej1u2kY NRahrTwBVHGiwupnky2C3+iaNyN868vMi4V62r+ZH3W7NuArGYOY+RNpxtB5cF4M ZN0ELkHRnwO37OuittGJXw/uIeSk4LRdvjDrGlxcte3an1dxHxHh/sHmql06+IDg 8llOU5Yb9S1ZzKa+VmL4UrpMeCts3Q== =Lo+s -----END PGP SIGNATURE----- --azRFbMc4OzYqnx7Mx8JQ7g90JXmBjF7RC--