From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from userp1040.oracle.com (userp1040.oracle.com [156.151.31.81]) by mail09.linbit.com (LINBIT Mail Daemon) with ESMTP id 330F6105633D for ; Wed, 5 Apr 2017 13:40:49 +0200 (CEST) To: Christoph Hellwig From: "Martin K. Petersen" References: <20170331163313.31821-1-hch@lst.de> Date: Wed, 05 Apr 2017 07:40:36 -0400 In-Reply-To: <20170331163313.31821-1-hch@lst.de> (Christoph Hellwig's message of "Fri, 31 Mar 2017 18:32:48 +0200") Message-ID: MIME-Version: 1.0 Content-Type: text/plain Cc: axboe@kernel.dk, linux-raid@vger.kernel.org, martin.petersen@oracle.com, snitzer@redhat.com, philipp.reisner@linbit.com, linux-block@vger.kernel.org, dm-devel@redhat.com, linux-scsi@vger.kernel.org, lars.ellenberg@linbit.com, shli@kernel.org, agk@redhat.com, drbd-dev@lists.linbit.com Subject: Re: [Drbd-dev] always use REQ_OP_WRITE_ZEROES for zeroing offload List-Id: "*Coordination* of development, patches, contributions -- *Questions* \(even to developers\) go to drbd-user, please." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Christoph Hellwig writes: Christoph, > This series makes REQ_OP_WRITE_ZEROES the only zeroing offload > supported by the block layer, and switches existing implementations > of REQ_OP_DISCARD that correctly set discard_zeroes_data to it, > removes incorrect discard_zeroes_data, and also switches WRITE SAME > based zeroing in SCSI to this new method. Very, very nice. I think this is the correct approach. I'm going to send two follow-up patches that allow us to use UNMAP for discards and WRITE SAME w/ UNMAP for zeroout. That appears to be the preferred configuration for most storage devices. -- Martin K. Petersen Oracle Linux Engineering