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Lunev" , Eric Blake , Stefan Hajnoczi , Paolo Bonzini Subject: Re: [PATCH v2 01/12] qapi/common: Clarify what IoOperationType is for In-Reply-To: <20261019182028.45305-2-hreitz@redhat.com> (Hanna Czenczek's message of "Mon, 19 Oct 2026 20:20:17 +0200") References: <20261019182028.45305-1-hreitz@redhat.com> <20261019182028.45305-2-hreitz@redhat.com> Date: Tue, 20 Oct 2026 07:58:29 +0200 Message-ID: <8733u0ud4q.fsf@pond.sub.org> User-Agent: Gnus/5.13 (Gnus v5.13) X-Archived-By: MIME-Version: 1.0 Content-Type: text/plain X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.111 Received-SPF: pass client-ip=170.10.133.124; envelope-from=armbru@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -23 X-Spam_score: -2.4 X-Spam_bar: -- X-Spam_report: (-2.4 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.329, 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_H3=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_PASS=-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: 2.1.29 Precedence: list List-Id: qemu development List-Archive: List-Post: List-Help: List-Subscribe: , Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org X-Spam-Status: No, score=-17.6 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_PASS, SPF_PASS,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=4.0.1 X-Spam-Checker-Version: SpamAssassin 4.0.1 (2024-03-26) on aws-us-west-2-korg-listserv-alma10-1 Hanna Czenczek writes: > The documentation for this type is a bit sparse right now, and > specifically does not explain why it is limited to read/write only; > "I/O operation type" could well imply this should distinguish a much > broader range of operations like flushes, discards, etc., but it does > not. > > Make a note why that is, which is that these types reflect the block > device on-error policy settings that we have, which are rerror for read > and werror for write. > > Signed-off-by: Hanna Czenczek > --- > qapi/common.json | 5 ++++- > 1 file changed, 4 insertions(+), 1 deletion(-) > > diff --git a/qapi/common.json b/qapi/common.json > index 1352e664b23..880eb87a9cb 100644 > --- a/qapi/common.json > +++ b/qapi/common.json > @@ -9,7 +9,10 @@ > > ## > # @IoOperationType: > -# An enumeration of the I/O operation types > +# An enumeration of the I/O operation types, limited to the block > +# device on-error policy settings we have (rerror and werror). > +# For reference, the corresponding error policy values are set in > +# `BlockdevOnError`. > # > # @read: read operation > # I believe I get what you mean only because I read the cover letter first. My first attempt I/O operation types that may have a block device on-error policy. is still confusing, because we use "block device" both for frontends and backends. I believe "block device on-error policy" refers to the qdev properties "rerror" and "werror" certain block frontends / device models have (virtio-blk-device, scsi-hd, scsi-cd, usb-storage). Possible clarification: These are the properties "rerror" and "werror" certain block device models have. And then maybe @read: read operation, corresponding to property "rerror" @write: write operation, corresponding to property "werror"