From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5F1F5EE14D6 for ; Thu, 7 Sep 2023 05:39:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234046AbjIGFjW (ORCPT ); Thu, 7 Sep 2023 01:39:22 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46190 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229488AbjIGFjV (ORCPT ); Thu, 7 Sep 2023 01:39:21 -0400 Received: from smtp-out2.suse.de (smtp-out2.suse.de [IPv6:2001:67c:2178:6::1d]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8C69B19BD; Wed, 6 Sep 2023 22:39:17 -0700 (PDT) Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by smtp-out2.suse.de (Postfix) with ESMTPS id 2C08A1F459; Thu, 7 Sep 2023 05:39:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_rsa; t=1694065156; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=vEzdXwzrXnDTeO0P+aNFlsgJ60oxO7RTr/+XEDVnWGU=; b=zr7k3C3k5bcifoR7lksFXR5wYxINEnL5SHX7Hgtw8PH/VB7pxIJltEsBEDIsWKJhtOBllg kjBlPikKsXRR3aBkuHtcwqVYAsGuRiCE+5YdeJ9Gj/nMdolzpBxh0W+LWzTQsmgCtsl0GU nx8up8cqOng/NvIWPUVsz5QE5LyTNmQ= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_ed25519; t=1694065156; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=vEzdXwzrXnDTeO0P+aNFlsgJ60oxO7RTr/+XEDVnWGU=; b=cwHd6RbV9kQqZVcKJLf2ZxshTikYkz2/zqjz1vx77H0a2bb63I00umYAVZa6h4IjnOM5ZK fpOti423Zoa7T8Ag== Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by imap2.suse-dmz.suse.de (Postfix) with ESMTPS id 7AB0513458; Thu, 7 Sep 2023 05:39:15 +0000 (UTC) Received: from dovecot-director2.suse.de ([192.168.254.65]) by imap2.suse-dmz.suse.de with ESMTPSA id r6UMGwNi+WQ6XAAAMHmgww (envelope-from ); Thu, 07 Sep 2023 05:39:15 +0000 Message-ID: Date: Thu, 7 Sep 2023 07:39:14 +0200 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v15 02/12] Add infrastructure for copy offload in block and request layer. Content-Language: en-US To: Nitesh Shetty , Jens Axboe , Jonathan Corbet , Alasdair Kergon , Mike Snitzer , dm-devel@redhat.com, Keith Busch , Christoph Hellwig , Sagi Grimberg , Chaitanya Kulkarni , Alexander Viro , Christian Brauner Cc: martin.petersen@oracle.com, mcgrof@kernel.org, gost.dev@samsung.com, Anuj Gupta , linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, linux-nvme@lists.infradead.org, linux-fsdevel@vger.kernel.org References: <20230906163844.18754-1-nj.shetty@samsung.com> <20230906163844.18754-3-nj.shetty@samsung.com> From: Hannes Reinecke In-Reply-To: <20230906163844.18754-3-nj.shetty@samsung.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 9/6/23 18:38, Nitesh Shetty wrote: > We add two new opcode REQ_OP_COPY_SRC, REQ_OP_COPY_DST. > Since copy is a composite operation involving src and dst sectors/lba, > each needs to be represented by a separate bio to make it compatible > with device mapper. > We expect caller to take a plug and send bio with source information, > followed by bio with destination information. > Once the src bio arrives we form a request and wait for destination > bio. Upon arrival of destination we merge these two bio's and send > corresponding request down to device driver. > > Signed-off-by: Nitesh Shetty > Signed-off-by: Anuj Gupta > --- > block/blk-core.c | 7 +++++++ > block/blk-merge.c | 41 +++++++++++++++++++++++++++++++++++++++ > block/blk.h | 16 +++++++++++++++ > block/elevator.h | 1 + > include/linux/bio.h | 6 +----- > include/linux/blk_types.h | 10 ++++++++++ > 6 files changed, 76 insertions(+), 5 deletions(-) > Having two separate bios is okay, and what one would expect. What is slightly strange is the merging functionality; That could do with some more explanation why this approach was taken. And also some checks in the merging code to avoid merging non-copy offload bios. Cheers, Hannes -- Dr. Hannes Reinecke Kernel Storage Architect hare@suse.de +49 911 74053 688 SUSE Software Solutions GmbH, Maxfeldstr. 5, 90409 Nürnberg HRB 36809 (AG Nürnberg), Geschäftsführer: Ivo Totev, Andrew Myers, Andrew McDonald, Martje Boudien Moerman