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Fri, 21 Aug 2020 14:11:37 +0000 From: Vladimir Sementsov-Ogievskiy To: qemu-block@nongnu.org Subject: [PATCH v5 01/10] block: simplify comment to BDRV_REQ_SERIALISING Date: Fri, 21 Aug 2020 17:11:14 +0300 Message-Id: <20200821141123.28538-2-vsementsov@virtuozzo.com> X-Mailer: git-send-email 2.21.3 In-Reply-To: <20200821141123.28538-1-vsementsov@virtuozzo.com> References: <20200821141123.28538-1-vsementsov@virtuozzo.com> X-ClientProxiedBy: AM3PR05CA0139.eurprd05.prod.outlook.com (2603:10a6:207:3::17) To AM7PR08MB5494.eurprd08.prod.outlook.com (2603:10a6:20b:dc::15) MIME-Version: 1.0 X-MS-Exchange-MessageSentRepresentingType: 1 Received: from kvm.sw.ru (185.215.60.171) by AM3PR05CA0139.eurprd05.prod.outlook.com (2603:10a6:207:3::17) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.3305.25 via Frontend Transport; Fri, 21 Aug 2020 14:11:36 +0000 X-Mailer: git-send-email 2.21.3 X-Originating-IP: [185.215.60.171] X-MS-PublicTrafficType: Email X-MS-Office365-Filtering-Correlation-Id: 4126218f-d288-480c-c881-08d845dc1e49 X-MS-TrafficTypeDiagnostic: AM6PR08MB5253: X-MS-Exchange-Transport-Forked: True X-Microsoft-Antispam-PRVS: X-MS-Oob-TLC-OOBClassifiers: OLM:7691; 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envelope-from=vsementsov@virtuozzo.com; helo=EUR03-VE1-obe.outbound.protection.outlook.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/08/21 10:11:37 X-ACL-Warn: Detected OS = Windows NT kernel [generic] [fuzzy] X-Spam_score_int: -30 X-Spam_score: -3.1 X-Spam_bar: --- X-Spam_report: (-3.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, MSGID_FROM_MTA_HEADER=0.001, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H2=-1, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001, URIBL_BLOCKED=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: fam@euphon.net, kwolf@redhat.com, vsementsov@virtuozzo.com, armbru@redhat.com, qemu-devel@nongnu.org, mreitz@redhat.com, nsoffer@redhat.com, stefanha@redhat.com, den@openvz.org Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" 1. BDRV_REQ_NO_SERIALISING doesn't exist already, don't mention it. 2. We are going to add one more user of BDRV_REQ_SERIALISING, so comment about backup becomes a bit confusing here. The use case in backup is documented in block/backup.c, so let's just drop duplication here. 3. The fact that BDRV_REQ_SERIALISING is only for write requests is omitted. Add a note. Signed-off-by: Vladimir Sementsov-Ogievskiy Reviewed-by: Stefan Hajnoczi --- include/block/block.h | 11 +---------- 1 file changed, 1 insertion(+), 10 deletions(-) diff --git a/include/block/block.h b/include/block/block.h index 6e36154061..b8f4e86e8d 100644 --- a/include/block/block.h +++ b/include/block/block.h @@ -53,16 +53,7 @@ typedef enum { * content. */ BDRV_REQ_WRITE_UNCHANGED = 0x40, - /* - * BDRV_REQ_SERIALISING forces request serialisation for writes. - * It is used to ensure that writes to the backing file of a backup process - * target cannot race with a read of the backup target that defers to the - * backing file. - * - * Note, that BDRV_REQ_SERIALISING is _not_ opposite in meaning to - * BDRV_REQ_NO_SERIALISING. A more descriptive name for the latter might be - * _DO_NOT_WAIT_FOR_SERIALISING, except that is too long. - */ + /* Forces request serialisation. Use only with write requests. */ BDRV_REQ_SERIALISING = 0x80, /* Execute the request only if the operation can be offloaded or otherwise